Category Archives: Teachers’ Resources

Agriculture Finest Notes Form One, Two, Three and Four

 

FARM STRUCTURES

Introduction

Farm structures are different types of physical constructions that are put up in a farm for the purpose of livestock and crop production.

These structures help increase efficiency of agricultural production.

Most of the farm production processes are carried out under controlled environment in order to maximize the output. For instance:

  1. Animals must be protected from rain, wind or high sunlight intensity in order to keep healthy.
  2. ii) Harvested crops must be protected from water, insects, fungi and extremes of temperatu

iii) Farm machinery must be protected from rain and dirt to keep depreciation level to a minimum.

Siting

Farm structures must be located in suitable areas for a farmer’s ease of use. Therefore, siting is very important in the construction of farm structures and buildings.

Sitting refers to locating an area where a particular farm structure or building is to be constructed.

Factors considered when site selecting.

(i)             Topography: If the land is too sloppy, there are high chances of landslide occurrence; and if it is too flat, there is likelihood of poor drainage that leads to flooding. A relatively flat free drained area is most suitable.

  1. ii) Prevailing winds and rainfall: Windbreaks are put perpendicular to the direction of wind to reduce wind velocity. Strong winds can destroy buildings. Site the farm buildings facing away from the direction of wind,and away from the direction of prevailing rains in order to minimize chances of water entering the buildings

iii) Soil type: Soil characteristics and strength determine its ability to withstand stress exerted by a building. Erect structures on firm, well-drained soils.

 

(iv) Nearness to utility sources such as electrical power lines, telephone lines and piped water: This allows cheaper access to essential services.

(v) Sewage disposal: The design must be in such a way that the lengths are in straight lines for ease of cleaning when blocked. The system should be accessible to a disposal vehicle.

(vi) Security: The area chosen must be secure against theft, vermin intrusion, fire or tresspassers.

(vii)Accessibility to roads:The farm structures and buildings should be located near the public road. This facilitates fast access of farm produce to the market.

 

Parts of a farm building

Most farm buildings comprise of the following parts:

(i) Foundation

It is made on the firm sub-soil.

They are laid to a depth of about I-2m depending on the soil type e.g. in clay soils, deep foundations are laid, while in sandy soils shallow foundations are made.

How foundations are laid

Farm building foundations are laid on a firm soil layer (i.e. sub-soil) since top soil has poor bearing capacity. Therefore it is recommended to dig down to a layer of firm soil. Trench work is done on site after marking out the foundation outline.

Set out and check the diagonals for accuracy, excavate the trench of at least 400 mm wide to allow someone to work in it. The sides of the trench are trimmed to get a straight, vertical and fair finished face of the sides.

(ii) Walls

They are vertical loaded parts of a building.

These can be made of stones, bricks, timber, blocks.

They should withstand side pressure from wind etc.

The wall should be strong to carry load of the roof and their own weight.

 

The type of materials used to construct the wall is determined by the following factors:

(i) Availability of the materials.

(ii) The use of the building.

(iii) Weather conditions of”the place.

(iv) Strength of the soil in the area.

(v) Cost of the materials.

(vi) Level of technology to be used.

 

iii) Roof

It protects the house from rain, sun, wind and cold.

It provides protection to the animals or stored crops from damage by adverse weather conditions.

Features of a good roof: must be leak proof, able to withstand the load of the roofing material, durable, fire proof and a good insulator of heat.

Cornmon roofing materials are: timber, steel and the roof covers are grass, galvanized sheets, asbestos, tiles, fiber glass, etc.

Roofing

Roofing is done after wall construction.

Procedure for roofing:

  • Positions of the post are marked.
  • Supports for the joints are prepared.

(iii)        Timber joints are then fixed on the supports.

  • Firming piece are fixed on the joints to provide the required fall

,

  • Tongues or grooved boards are fixed on the joints covering the whole roof surface.
  • Fascia boards are nailed at the lower and sloping edges of the roof to conceal the joints. Gutters are fixed to collect water from the roof.

 

Types of farm buildings

Livestock buildings and structures

These are structures used for handling livestock during various routine management practices or for housing the livestock.

They include: crushes, dips, spray race, calf pens, dairy shed/parlour, poultry houses and structures (deep litter, coops, folds/arks, runs, battery cages), rabbit hutches, piggery/pig sty, fish ponds, silos, zero grazing unit, bee hives.

 

 

 

  1. Crushes

These are used for restraining an animal when carrying out certain livestock routine practices, such as, spraying and milking.

Crushes have a holding yard and consist of a head rail and a horizontal split which allow easy access to the sides of the animals’ body.

The horizontal and vertical bars aid in fixingthe animals’ head during dehorning.

The tad bar at the entrance holds an animal in.

There is an open gate at the front of the crush to allow exit of the animal.

A crush is used while carrying out the following operations:

  • Hand-spraying or hand dressing to control ectoparasites (ticks).
  • Drenching animals against internal parasites.
  • Vaccination against diseases.
  • Artificial insemination.

 

  • Applying identification marks e.g. branding, ear notching.
  • Taking body temperature of an animal.
  • Close examination of sick animals.
  • Milki
  • Pregnancy diagnosis .

Examples of the crushes:

(a) A three post crush: Normally used when handling one animal.

(b) A crush for a small scale farmer: It is longer than the three-post crush.

Its length is 3 m and width is 1 m.

(c) A crush for holding many animals: This is mainly used during vaccination of livestock.

Management of animals in a crush

  • Animals should be arranged in a single row. Animals of the same ageshould follow one another.
  • Care should be taken to prevent the bunching of animals together.
  • Animals should move towards one direction only.
  • Restrain vicious animals.

Maintenance of a crush

  • Repair any broken or worn out posts and rails.
  • Apply old engine oil on the post made of timber to prevent destruction by termites. Carry out regular checks for any loose frames.
  1. Dips

It is a farm structure designed to accommodate a chemical dip wash in which animals are immersed for the purpose of controlling ticks.

Components of a dip

  1. Collecting yard

It is used for holding animals before dipping. It should allow for about 2 m? space per ( cattle) head. There should be a water trough for animals to drink before dipping. The floor should be built of waste quarry stones to help remove mud from animal hooves.

  1. Foot bath

Its purpose is to wash hooves of animals so that they are free of mud. It contains copper sulphate solution to control foot-rot disease. The number of footbaths depend on the soil type. One or two footbaths may be placed at the dip entrance.

  1. The jump

This is a narrow entrance to the dip tank with short steps. It is 34-45 em above the dip wash level hence it allows for maximum immersion and enables dip wash splash to return into the dip .

  1. Dip tank

This is where animals are immersed. It contains the acaricide solution.

  1. Draining race

It helps in recovery of the excess dip wash back to the dipping tank. This is possible since it has a sloping floor towards the dipping tank. It should be water tight, rough and have no cracks, pot holes and long enough to increase the back flow of water.

  1. Silt trap outlet

Mud and dung in the dip wash is trapped here as it flows back to the tank from the draining race. This helps to reduce siltation of the dipping tank ..

  1. Roof

It is made using corrugated iron sheets to reduce evaporation and dilution of the dip by direct sun and rain water, respectively. It is also referred to as dipping tank shelter. It may be used to trap rain water for use in the dip.

  1. Soaking pit

Used for dumping sediments from the dipping tank. This ensures no pollution of the environment.

Types of  dips there are two types of dips

·       Plunge dips

·       The machakos dip

·

Factors to consider before constructing a dip

 

 

 

 

 

 

 

 

 

 

  • Nearness to the grazing areas so that animals do not walk for long distanc
  • The site should be on a firm ground to be able to withstand the pressure exerted on the ground by trampling of liv
  • Good drainage of the construction site. This minimizes flooding in the surrounding areas that could lead to dilution of the dip wash. It also reduces soil erosion which causes siltation in the dipping tank.

Cattle management at the dip

(i)   The frequency of dipping depends on the tick infestation level, otherwise once or twice per week is adequate.

(ii) The best time to do the dipping is in the morning or during cool weather. (iii) Provide the animals with drinking water before dipping so that they are not tempted to drink the acaricide solution.

(iv)First, run 10 -15 animals through the dip so that they mix the dip wash, then Dipthem a second time.

(v) Animals should be arranged to enter the dip in a single file.

(vi) Do not dip sick, injured or pregnant animals and too young calves. (vii) Dip the animals according to their ages.

(viii) Dip all the cattle the same day.

(ix) Keep records of all the animals dipped.

Maintenance of a cattle dip

. Regular testing of the dip-wash by use of a dip-testing kit to keep the dip chemical strength ‘at the correct concentration.

Clean foot bath before and after dipping.

Lock securely the entrance and exit to the dip to prevent access by intruders or stray animals.

Drain away the dip wash carefully to avoid the contamination of pastures and nearby water sources.

Ensure the roof of the dip is leak-proof to keep off rain water. Replenish dip wash by topping its level as necessary.

Repair any cracks in collecting yards, foot baths, dipping tank, silt trap, draining race and walls.

Advantages of a plunge dip

  • Many animals can be dipped in a single oper
  • Because of the replenishment of the bath, it can be used several
  • The cost of dipping is low due to less wastage.
  • Requires less technical skills and labour than a spray race.
  • Every part of the animal is reached by the solution due to total immersion of the animal’s body.

Disadvantages

  • There is risk of excessive dilution of the dip wash due to evaporation during the dry season or by rain water, or by impurities introduced by the animal and through leakage at the bottom or cracks at the sides.
  • It cannot be used on sick, heavy, young and pregnant animals.
  • The spread of viral diseases e.g. foot and mouth is possible through dipping of infected animals.
  • It is cumbersome to replenish or empty it.
  • There is a high initial cost of construction hence individual farmers cannot afford it.
  • Maintenance costs may be high due to repairs of the cracks and purchase of repair materials.
  1. Spray race

This is a structure used for tick control.

Its main principle of operation is showering of animals with an acaricide rather than immersion. Animals walk through a confined area (race) where a pipe system with many nozzles (usually 20 – 30) are fitted at certain intervals and at particular angles.

The animals are wetted as they walk through the length of the race with dip-wash sprays coming through the nozzles.

The nozzles are placed at strategic places on the side, floor and overhead pipes and at such angles that the animal gets wetted from all sides.

The wash is drawn from a reservoir besides the race through a centrifugal pumpdriven by an engine or tractor and is circulated under pressure through the piping to the nozzles.

Components of a spray race

Delivery pipes with nozzles:

The pipes are made of metal to withstand the pressure of the spray wash. The pipes run on the floor, the side walls and overhead and are fitted with nozzles which release the spray wash at appropriate points. The pipes are joined as two suction pipes originating from a reservoir tank.

The side walls:

They may be made of concrete blocks or stones. They provide a secure enclosure for the animals being sprayed and prevent the spray drift i.e. being swept away by wind.

Guard rails:

These are made of metals and guide the animals through the spray race.

Control valve:

This is the valve used to open the delivery pipes for chemicals to flow out.

Reservoir tank:

This is the tank which contains the acaricide.

Agitator pipe.

The pipe that maintains pressure to ensure that the chemical is properly mixed.

Suction pipe:

It sucks the chemicals under pressure from the reservoir tank and is connected to ‘the delivery pipes.

Filter mesh:

            Filters any foreign materials from the spray wash draining back into the reservoir tank.

Pressure gauge:

It ensures that the machine is operating under correct pressure.

Drainage pipe:

When the chemical needs to be replenished, the drainage pipe is used to clear the tank.

Power source:

This is used to drive the machine. It can be tractor P.T.O shaft, electricity, etc.

Maintenance of a spray race

(i)   Pump out dirty spray wash into a safe disposal pit in a fenced area. Great care should be taken to avoid contamination of pastures and water sources.

(ii) Clean the nozzles to avoid blockage so that the acaricide gets out with ease during spraying.

(iii) Leave some wash in the pump to keep the foot valve in working condition and prevent cracks in the pump floor.

(iv) Repair any leakages/cracks in the side walls

 

Stock management at the spray race

  • Arrange the animals in a single file as they enter the race.
  • Check to ensure that the animals lift their tails as they walk through the length of the tunnel so that under tail wetting takes place.
  • Clip the hair in the ears inner surface and tail switch for better wetting.
  • The young and new animals should be encouraged to go through the race by lowering the amount of pressure and later increasing the shower pressure.

Advantages of a spray race

  • It is faster and can spray more animals per hour than a plunge dip.
  • Suitable for pregnant, heavy, young, goat, sheep and sick animals as they do not get shock.
  • Fresh wash every spraying time.
  • It is economical.
  • It is less laborious.
  • No poisoning of animals due to swallowing of the acaricide

Disadvantages

  • It requires high technical skill to operate and ma
  • In wet weather, the nozzles may get clogged with dirt found in the wash.
  • It is only economical with a large her
  • High initial cost of construction.
  1. Dairy shed/parlour

A dairy shed is part of the dairy unit that is used during milking.

It comprises of the following parts:

  • A night shade.
  • A calf pen which should be fitted with a feed and water trough.
  • A feeding and watering area.
  • The milking section.
  • A feed and equipment store.

There are two types of milking sheds:

  1. Permanent milking shed:

This has a milking machine permanently installed at the milking section.

  1. ii) Movable milking shed:

. These units are fitted with small wheels which facilitate their movement to different sites.

Movable milking sheds are common in large dairy farms.

Cows are fed on concentrates while in the parlour.

Factors to consider in the construction of a dairy shed

  • Resting area:

Gives the cow room to rest and chew the cud.

(ii) should be spacious enoughto allow room for exercise enhancing proper physiological body functioning.

(iii) shouldhave adequate feeding and watering space. It is important to separate these from the resting area to avoid accumulation of dung and urine around the feeding and watering points.

(iv) Separate milking area from the feeding, watering arid exercise areas .

.

(v) should have a feed and drugs store and milking equipment.

(vi) Calf pens must be near the dairy shed.

(vii) Provision for proper waste disposal.

(ix) The floor of the milking section, feeding, watering and exercise area need to be built of concrete to withstand the weight of the cattle and facilitate cleaning.

Maintenance of a dairy shed

  • Repair worn out or broken parts immediately they are notice
  • Clean the dairy shed regularly with detergents and disinfectant
  • Ensure proper drainage in the surrounding area.
  • Ensure proper ventilatio
  1. Calf pens

These are structures for housing calves.

The calf pen can be either communal or individual.

Individual calf pens are most suitable

Theyprevent cross-suckling among calves which results in hair balls in the rumen,

Provide for better individual attention given to the calves

Minimize spread of diseases.

Calf pens should be located near or within the dairy unit.

 

Features of a good calf pen:

  • It should provide complete separation of calf from other calves thus eliminate

the chances of navel suckling and spread of diseases.

  • It should be easy to clean. This prevents accumulation of dirt.
  • It should be spacious.
  • It should allow the calf to see the mother cow and other animals.
  • It should provide facilities for individual feeding and watering.
  • It should allow the calf to have access to sunlight.
  • It should be well. Ventilated to prevent infection.
  • It should be durable.
  • It should be economical to construct.

 

Types of calf pens:

  • Permanent calf pens:

These are fixed on the ground and cannot be relocated to other areas.

They are prominent in the zero-grazing method of livestock rearing.

  • Movable calf pens:

These are mobile and can be relocated to new sites as a farmer may decide.

They are most common in the paddocking method of animal grazing.

Maintenance of a calf pen

(i) Clean the calf pen regularly.

(ii) Repair leaking roofs to prevent wetness of the floor.

(iii) Repair any worn out parts.

(iv) Paintthe walls white to keep off flies. White wash is preferred.

(v) Ensure there is proper ventilation.

  1. Poultry houses and structures

These are housing structures used for poultry production.

They should be sited in free draining areas and away from main house.

  • All the structures must provide warmth,
  • Be properly lit and
  • Wellventilat
  • They should be kept damp-free.

They include :

  1. poultry shed run,
  2. deep litter,
  • battery cage,
  1. fold/ark: •

(a) Poultry shed and run

This structure has a shed and run and is sometimes attached to a nest box.

The run is enclosed with a chicken wire.

It has a door for use by the keeper to gain entry into the run when there is need.

The shed should preferably be made of wooden walls.

It provides protection against bad weather and predators.

It must be properly ventilated to allow free air circulation,easy to access for cleaning, collection of eggs and for the arrangement of feeding troughs. Place nest boxes inside the shed. The stand must be fitted with rat guards to prevent entry of rats into the shed.

(b) Battery cage system

These are the structures used to house birds under the intensive system of poultry production.Individual birds or a few birdsare confined in cages or batteries arranged from side to side. The size of the cage is about 0.5 m-per hen. A 10 cm length of feed trough should be allocated per cage. The farmer can, however, have one long feed trough that runs through several cages in each tier. Battery cage can be multiple tier, stair step or flat-deck.

Advantages of the battery/cage system

  • Less spread of parasitic diseases ego worms and coccidiosis since the birds do not come in contact with their droppings.
  • Less feeding cost. This is because the birds have little exercis
  • Culling is easy since one can easily identify the less productive birds easily.
  • No broodiness in hens since they do not come in contact with the eggs.
  • Farmer gets clean eggs.
  • Accurate production records are easily kept.
  • Reduced incidents of feather-plucking, cannibalism and egg-eating vices.

 

Disadvantages of battery/cage system

  • High initial capital.
  • Higher maintenance costs where automation is used.
  • Birds may get fatigue due to lack of exercises lowering their productivity.

(c) Coops

These are specialised types of cages that are used for rearing hens that are brooding. They are commonly used in small scale, non-commercial poultry rearing systems.

(d) Fold/Ark

It has both the run and the shelter section.

The run is covered with chicken wire mesh.

It provides birds with space for exercise and to get natural vegetation and insects.

The shelter part of the fold is covered with solid materials to provide protection against predators and bad weather conditions.

The fold is moved to new sites at regular intervals to reduce the accumulation of bird droppings. One fold can carry up to 25 birds. Normally a fold measures about 3.5 m x 1.5 m wide x 1.5 m high.

  1. e) Night shelters

These are used in free range system where birds are allowed to move within a fenced enclosure called a run.

Birds spend the night in these shelters but are allowed to go out and scavenge for food during the day. These structures are also equipped with laying nests.

The night shelters are mostly used by small-scale, non-commercial poultry keepers.

Night shelters are raised off the ground by use of stands or hung on a tree to keep off predators. Movable house shelters are preferred as they prevent build-up of parasites and diseases.

  1. Deep litter

This is a poultry house where birds are confined.

A deep litter has a low masonry wall of 0.6 m on the leeward side.

The rest of the upper part is made of wire mesh.

The floor space should allow for 4-5 birds/m2.

The house should contain laying boxes and perches for the hens.

Keep the roof leak-proof and avoid dampness in and around the house.

The building must keep away stray birds, predators and rodents.

 

Features of A good deep litter

  1. Well ventilated: The leeward side should have walls up to 1.5 m but not below 0.6 m. The rest of the upper section is made of wire mesh.
  2. Draught-free: The wall section facing the windward side should be solid from bottom to top .:
  3. Litter size: The litter on the floor must be between 15 – 30 em deep. This helps to keep the poultry house warm and absorb birds’ droppings. The litter should be kept dry.
  4. Spacious: The house must be spacious enough to accommodate the number of birds reared without overcrowding. There must be enough space for each bird i.e. 4 – 5 birds per m”.

 

Advantages of deep litter housing

  • Easy access to the feeds and water by birds.
  • (ii) Easy collection of eggs.

(iii) Regular cleaning of the house is not necessary since the litter absorbs the droppings.

  • Allowshigh stocking rates.

 

Disadvantages of deep litter housing

  • Eggs become dirty since most birds lay on the litter.
  • (ii) It is difficult to identify non-laying birds.
  • Cannibalism and egg eating vices are com
  • (iv) Diseasesspread easily within the flock.
  • High cost of building deep litter house

 

Maintenance practices of poultry houses

  • Regular cleaning and disinfecting of the poultry houses.
  • Ensure roofs are leak-proof.
  • Minimize entry of dust into the poultry Dust is a predisposing factor

to respiratory infections in birds.

  • Put the poultry house into a resting period before start of a new project.
  • Repair broken parts of the structure.
  • Dusting should be don~ regularly to control external parasites.

 

 

Rabbit hutches/Rabbitry

These are houses for keeping rabbits.

The house should be painted white to reflect much of the solar radiation that causes sunburn in rabbits.

A rabbitry unit is divided into two parts: The feeding and watering area and the resting and exercising area. A wire netting of 1 cm mesh or wooden slats fixed 1 cm apart can be used for the floor. It has a hinged door for easy opening and closure.

The hutch is fitted on stands of about 60 cm above the ground. Inside the hutch, provide feed and water troughs and a nest box of size 38 cm X 25 cm X 20 cm.

Place the hutch under a shade and in a site protected from the prevailing wind direction.

 

Features of a good rabbitry

  1. Adequate ventilation and well lit but protected from direct sun rays.
  2. .Spacious: Space requirement for a doe is 80 – 115 cm”.
  3. Must be protected from direct rain and wind.
  4. The sides and floor of the hutch should have chicken wire mesh.
  5. The rabbitry must be safe from predators and pests like dogs, cats and snakes
  6. It should be raised off the ground.

The floor of a rabbit hutch may be made of solid wood or wire mesh.

The advantage of a solid floor is that it allows for comfortable placement of bedding materials which help prevent hock sores in rabbits.

It also allows rabbit cages to be stacked in tiers.

However, its disadvantages are that it is difficult to clean, and that feeds and water can be easily contaminated by the droppings.

The advantages of a perforated floor or a wire mesh floor are that they are self cleaning since the droppings and urine pass through easily, and the contamination of feeds and water is much reduced.

 

Maintenance of a rabbit hutch

  • Repair broken parts.
  • Repair leaking roof to prevent dampness inside the ra
  • Paint the wooden posts to last long. Apply old engine oil to keep off ants.
  • Clean regula

Piggery /pig sty

Pigs are housed in a structure known as piggery or pig sty.

Pigs are very sensitive to extreme weather conditions, therefore a piggery should provide warmth and bewell ventilated.

.

Essential features of a piggery

Farrowing pen

It is used for farrowing and ensuring the safety of the piglets.

The pen is provided with a farrowing crate to prevent the sow from lying on the piglets and a heat source to protect the piglets against chilliness.

It contains a creeparea where only the piglets can access creep feed.

Weaners pen

It is where weaned pigs are kept.

It should have a feeding, watering and resting section.

Boar pen

This is where breeding boars are kept.

It allows room for sows to be served during the breeding season.

Gilts pen

It is used for keeping young female pigs up to the age of service (usually 12 months).

Fish ponds

 

 

These are structures that are constructed in the farm for rearing fish.

Fish ponds require a large amount of water; therefore it is important to construct them near a water source such as a stream or a river.

The water should come from a higher ground so that it flows downhill into the fish pond and be drained out easily.

The site of a fish pond must be well selected for successful construction and maintenance.

 

Procedure of establishing a fish pond:

(i)             Site selection: Select a suitable place where water flows gently from the source.

The ground soil of high water-retention capacity is preferred.

(ii) Site marking: After selecting the site, use pegs to mark the channel from the river, the entrance and exit of the pond, and the channel to take water back

into the river.      •

  • Clearing the land: All vegetation is cleared off the site of the pond area.
  • Digging the pond: Soil is dug out. The top soil is placed in a particular place as it will be reuse The upper side of the pond is dug 0.5 m deep and the lower side of the pond 1.5 m.

(v) Construction of dyke: The dyke is the wall constructed all round the pond.

Pond floor

(vi) A cone is established by digging a trench 0.5 m wide and lower than the general level of the pond bottom. It is then filled with clay soil and compacted or concrete is used to help prevent water seepage.

Parts of a fish pond

 

Inlet:

This is the canal or a pipe that brings water into the fish pond.

It is made in the dyke slightly above the level of the pond water.

A screen of fine mesh is filled across the inlet to prevent the entry of undesirable species of fish into the pond.

 

Outlet:

This is made at the deeper end of the pond just a little above the bottom of the pond.

A pipe is connected to it to make the outlet firm.

A screen is fittedat the mouth of the outlet to prevent the fish from escaping from the fish pond.

It is used to drain water back into the river during harvesting.

 

Spill way:

It is the channel that allows removal of excess water from the pond.

It is made at the top of the dyke on the lower side of the pond.

The spillway prevents

the water from overflowing on the dykes.

Factors to be considered when siting a fish pond

 

(i) Topography: The selected area should be gently sloping. This allows easy flow of water into and out of the pond. It also helps avoid flooding of the fish pond.

 

(ii) Accessibility to the fish pond:It should be located near the homestead or where it can be reached easily.

 

(iii) Security of the area:The site must be protected from tresspassers, thieves or predators such as mongoose, kingfishers, etc.

(iv) Free of pollutants from sewage and dumping sites.

 

(v) Nearness to water source: A fish pond should be constructed near a reliable water source. This ensures an adequate water supply.

 

(v) Soil type:The ground where the fish pond is constructed must have soils with a high water retention capacity to minimise water seepage. Clay soil is preferred.

 

Care and maintenance of the fish pond

(i) Feed the fish daily.

(ii) Fertilize the pond twice a week.

(iii) Check on the water level in the pond regularly and top up when necessary.

(iv) Repair any leaking parts of the fish pond.

(v) Remove aquatic weeds around the pond.

 

Silos (for silage)

These are structures used for preparation of silage. There are different types of silos. The most common are:

  1. i) Pit/Trench silo.
  2. ii) Tower silo.

iii) Clamp or bunker silo.

 

In siting silos, consideration should be made for access to loading and proximity to the zero-grazing unit.

Tower silo

 

This is made of concrete above the ground. The concrete wall is usually perpendicular on three sides, leaving one side open for the filling and removal of the silage. The floor of the tower silo can be cemented or lined with polythene sheet.

 

Materials used to construct silos are timber, compacted soil, and polythene sheets.

Clamp or Bunker silo

. This structure is constructed above the ground level. Its sides or the walls are slanted. The silo is usually constructed using timber.

Zero grazing units

This is a structure for housing livestock in total confinement.

The animal is fed in the unit and is rarely moved out.

The zero-grazing unit comprises of: a feeding area, milking section, sleeping area, feed store, and calf pen, milk recording room, feed preparation section and dunging area.

 

The floor is preferably made of concrete for ease of cleaning while the walls can be made of timber, bricks, stones, meshed wire, metal columns, pipes or iron sheets.

All sections of the unit are roofed except the resting area where the animal does exercises and gets sunshine.

Roofing material may be iron sheets or grass.

 

Bee hives

These are structures in which bees are kept.

There are many types of bee hives used by farmers in Kenya.

But the most common ones are log hive and Kenya Top Bar Hive (KTBH).

Types of bee hives

  1. 1. Log hive

It is made of a hollow log which is split into two parts, one being larger than the other.

The larger part is made into a trough­shapedstructure by removing the inner tissues of the log stem using a sharp chisel.

Holes are then drilled on the sides. The smaller part forms the floor board.

The two parts are tied together using wires.

  1. Boxhive

Made of sown timber cut to length of 1 m.

The best timber size for a box hive is one metre long with the inner area measuring 30 cm x 30 cm. The top side and end boards are nailed together while the bottom board is attached by means of wires or supported by 4 small pieces of timber which are detachable.

For ventilation and entrance of bees, holes are drilled in the bottom board, two near the ends and one in the centre.

  1. 3. Kenya TopBar Hive (KTBH)

This is a wooden box. It has long sloping sides which incline at an angle of 65°.

It has a series of bars forming the top of the hive where the bees attach their combs.

The bars allow for easy inspection of honey combs and honey harvesting since they can be removed and replaced easily.

Each bar measures 3.2 cm wide by 48 cm long.

The hive measurement is 90 cmlong, 48 cm wide at the top and 23 cm base width.

The top has a cover made of iron sheet with a wooden frame used for covering the hive top.

Coat the hive with wood preservative to protect it from insect damage or effect of rain water:

The hive has wide loops attached to its upper section used for its hanging it. KTBH is a modem bee hive and is the most widely used in East Africa.

 

Advantages of the Kenya Top bar Hive

  • The top bars can be easily removed and replaced during inspection of the combs.
  • Honey combs are removed without disturbing the br
  • Easy to construct and repa
  • A queen excluder can be used in the centre of the hive to separate honey from the brood.

Disadvantages

  • Top bar hives are expensive to construct.
  • Combs built on top-bars require careful handling to prevent breakage.
  • Top bar hives are not easily moved from one location to another without breaking the combs.

Maintenance of the Kenya Top bar Hive

  • Repair leaking
  • Replace the broken and worn out bars or sides.
  • Ensure that there are no spaces between the bars.

Farm stores

These are structures that are built for storage of seeds, animal feeds, farm tools, chemicals and crop produce that are used in crop and livestock production. There are various farm stores used for different purposes e.g. grain stores, feed stores, chemical stores, machinery stores and tool stores.

Feed store

These are houses constructed for keeping livestock feeds.

Most farmers normally buy feeds in bulk for use over a longer period of time.

Features of a good feed store:

  1. Spacious: To allow easy movement when placing and removing the feed.
  2. Easy to clean: Proper hygiene must be observed in the feed store to prevent contamination of the feeds.
  • Easy to load and off-load.
  1. Damp-proof: Free from moisture.
  2. Rodent free: It should contain raised crates for holding feeds and should have rat guards.
  3. Proper ventilation: To allow free air circulation.

Farm produce store

These are structures used for storing cereal produce such as maize, millet, sorghum, wheat, finger millet.

They can also be used to store pulse crops e.g. peas and beans.

Requirements of a good farm produce store:

(i)   Damp proof:Ensure the roof is not leaking, and that there are no cracks on solid walls. Dampness encourages fungal or weevil attack on the grains. Preferably construct a store raised off the ground i.e. about 60 cm above the ground.

(ii) Easy to clean: Good hygiene is very important for successful storage of farm produce. Therefore it is necessary that the store be easy to clean.

(iii) Verminproof: Rodents such as rats, mice can cause great damage to the stored produce. Prevent entry of such rodents by fitting rat guards or deflectors on the posts.

(iv) Should have proper ventilation to allow free circulation of air.

The size and type of farm produce store depend on:

  • The amount of the crop produce to be s There is need to construct a

big store for storing large amount of farm produce.

  • Specific storage needs of the crop e.g. temperature and relative humidity.
  • Availability of materials for construction.
  • Cost of the materials.
  • How the crop is to be stored e. shelled and un shelled maize have different

space requirements.

Types of farm produce stores

Stores vary from plastered baskets for small quantities of grain to silos for large quantities of grains, usually in tonnes.

They include:

  1. Sheds

 

Constructed for temporary storage of grains during harvesting.They are reinforced with wooden or metal pillars and have a water proof slanting roof.

  1. Godowns

 

These are more permanent structures for bulk storage of food grains.

They can also be used to store farm inputs like fertilizers.

They _are normally leased to farmers since they are expensive to construct.

  1. 3. Silos

 

A silo is an airtight storage facility that is specially constructed to allow easy loading and off loading of grain.

Most modern silos are fitted with conveyor belts to transport the grains up or down the silo.

4.Bins

These are made of steel, aluminium or concrete and are normally circular in shape. Improved grain bins have the following features:

  • They are raised above the ground to avoid dampness and prevent moisture

entry.

  • Have rat guards on the supporting post
  • Have impermeable walls to guard against rain water.
  • Have proper ventilation to control temperature variations.

Have proper roofing to protect grain from sunlight and rain

Basket granaries

Construct a platform on which the basket can rest. This helps prevent moisture from reaching the baskets. The granaries should be made air tight by plastering. Dust them with insecticides to prevent insect attack. Instal rat guards on base posts.

  • Gunny bags

These are stored in a structure that is free from dampness, insect attack and rodents.

Advantages of gunny bags

  • Gunny bags can be easily isolated and labelled to contain different grain products without the risk of mixing grai
  • Gunny bags can be easily moved, especially when transferring the stored products.

Machinery store

These are structures where farm machinery are kept. Such machinery include tractors, trailers, combine harvesters, etc.

The store should be spacious enough and secure to guard off thieves or burglars. The store should be constructed with strong building materials i.e metal bars, bricks concretes. It should be accessible to the farming fields or the main house in the homestead.

Tool store

This is the structure where small garden tools, livestock tools and workshop tools are. kept. It is also referred to as a tool shed. It should be spacious, preferrably contain a tool rack and have a roof to shelter it from rain and direct sun. The wall must be solid and constructed using timber, bricks or iron sheets. Ensure the tool store is always dry and cleaned at regular intervals.

Chemical store

These are structures for safe keeping of various chemicals. The common agro­chemical substances include: acaricides, pesticides, herbicides, drugs for injection or vaccination purposes, disinfectants, rodenticides and fertilizers.

It is important that chemicals be safely stored away from reach of children or people and fire sources. The chemical store should be made of bricks, stones or strong corrugated iron sheets. They must be damp-proof, have leak-proof roofs and be kept clean always.

Provide lockable cabinets for safe storage of the chemicals. Vaccines require special storage facilities like deep freezers.

General maintenance of farm stores

  1. Regular cleaning. Dusting of farm stores must be carried out frequently.
  2. Maintain good hygiene around the farm s
  3. Repair broken or worn out parts e.g. leaking roofs, broken doors, cracking walls.

Fences in the farm

These are structures that enclose designated areas and form physical barriers for animals and human beings restricting their movement within the enclosed area or preventing their entry into the enclosure. Any type of fence must allow easy entry and exit of livestock, people, and farm machinery through the designated entrance or exit areas.

Importance of fences in a farm

  1. Perimeter fences establish boundary lines which help reduce land disputes between neighbours.
  2. Fences keep out intruders e.g. trespassers, thieves, straying wild animals, etc.
  3. Rotational grazing is more effective through paddocking of the fields.
  4. Live fences act as windbreaks. This helps to reduce wind erosion or lodging of weak stem crops such as maize.
  5. Double fencing is an effective measure for controlling ticks.
  6. Diversified production. Fences protect crop from damage by animals where mixed farming is practised.
  7. Fencing enhances control of diseases and parasites by restricting movement of livestock. Stray animals from other farms are kept off.
  8. Facilitate the isolation of sick animals or pregnant cows, etc.
  9. Helps a farmer to carry out control breeding through ensuring the animals are grouped as designed by the farmer. It eliminates random mating or inbreeding.

Types of fences

  1. Barbed wire fence

These are fences made of barbed wire. They are commonly used in fencing cattle ranches. A single wire fence consists of 4-5 lines of barbed wire depending on the resources available.

It easily causes injury to farm animals by making cuts on the animals’ body. In sheep, it removes fleece.

Advantages

(i) Effective in controlling livestock and wild animals. (ii) Fairly cheap to establish.

Disadvantages

(i)   Can hurt the livestock by pulling or tearing parts of their body, which may lead to infections and lowers quality of hide.

(ii) Less durable, especially, the posts which can be easily attacked by ants and termites.

  1. Plain wire fence

It is ideal for fencing farms where sheep, goats and dairy cows are kept. About 6-8 lines of the wire can be fitted to a height of 70-90 cmabove the ground. A wire of thickness 3.25 – 4.0 mm is recommended.

Advantages

  • Do not cause injury to livestock.
  • (ii) It is cheap to maintain.
  • Easy to handle during fencing.

 Disadvantage

Animals can go through it very easily since it is not pricky.

  1. Electric fences

These are made of plain wires that conduct electricity. The wires are fixed on movable metal posts.

A portable low voltage battery is used to supply the electric current which gives a small shock to an animal when it comes into contact with the wire. It is mainly used in strip grazing and in the fencing of high potential or valuable crops prone to destruction by wild life. It is also used to protect high security areas such as homesteads, military barracks, game reserves, etc.

Advantages

  • Durable once installed.
  • (ii) Can easily be relocated.

(iii) It is very effective in protecting crops from big wild game. Disadvantages

(i) Unapproved electric controller units can be dangerous.

(ii) May become less effective when grass, weeds or shrubs touch the wires. (iii) Requires constant recharging of the battery.

  • Expensive to maintain and construct.

 

  1. Wall fences

These are made of stones, bricks or concrete blocks and are mostly used around farm buildings in urban areas to keep off intruders. They are expensive to construct.

  1. Chicken wire fences (wire mesh)

They are used for fencing poultry runs.

The thin gauge hexagonal open mesh is used to control movement of birds.

The mesh netting is embedded 15-30 cm into the ground and one metre above the ground to keep off intruders such as goats, sheep, pigs, poultry.

  1. Wooden fences

These are the most economical to construct where timber is available. However, wooden fence is susceptible to attack by termites and fungi. It is also less durable

and can catch fire easily.

 

  1. Live fences

These are formed from growing trees e.g. Kei apple, Mauritius thoms, Lantana camara, cactus, bougainvillea, sisal and cypress. They are slow to establish and are not effective in restricting the movement of animals. They act as good wind breakswhen mature and form hedges

Gates

(i)        Gates should be hinged on posts separate from the fence post.      ,

(ii) Most farm machinery require 4.3 – 4.6 m width of gates for easy passage.

(iii) Entrance or gates for pedestrians can be accommodated within the fence.

 

Gates can be made of timber or barbed wire. Passes are constructed using strong poles.

 

Fence reinforcement

This is done by use of struts, brace posts and droppers. The struts (brace post) are used to reinforce the strength of the fencing wire and are normally placed at the comers to prevent the king post (comer post) from bending inwards.

Droppers are fixed in between the standard posts. They must be dry and should not touch the ground.

Maintenance of the fences

  • Repair any broken part of the fence.
  • Strain the wire if loose, particularly for barbed or plain wires.
  • Trim overgrown branches of live fences.
  • Clear the fence lines to destroy habitats for rodents.

 

 

  • Tools and materials

Tools used in construction of fences are:

Pegs– –                        used to set out position for holes.

Claw hammer–           driving in nails/staples.

Bow saw–                    cutting branches on the posts.

Hand saw–                  cutting posts to the right length.

Wood chisel– boring holes and slots on the posts.

Pair of pliers–             cutting the wires.

Drill/auger bit–           boring holes in posts.

Soil auger–                  digging holes on the ground.

Claw bar –                  removing staples.

Mallet–                        hitting the chisel when making slots.

Wire strainer/stretcher– straightening the wires.

Tape measure–           measuring distances.

Ramming rods–           firm soil around the posts.

Panga-                        shaping pegs.

Axe     –                       splitting the posts.

Materials:                   Wires, staples, nails, post, droppers

Green house

Meaning

It is an enclosed structure used for raising tender plants which require a controlled environment to grow.

The structure provides optimum environmental conditions for the crops.

The structure must be able to withstand strong winds, rain, hailstones, snow, etc. It must also allow as much light as possible to filter through for plant growth.

The structure is designed in such a way that the crops can be handled efficiently, with minimum labour.

The crop environment is highly controlled.

Construction materials for green house

The following are the common construction materials for green houses; aluminium, steel, wood, glass, fiber glass, reinforced panels, acrylic panels, polycarbonate panels, plexi glass and rigid polyvinyl chloride, polyethylene and polyvinyl fluoride films.

(a) Covering material

Must be clear enough to provide optimum light transmission, be durable and economical. However, the structural components required to support it are usually costly.

Types of covering material:

(i) Fiber glass

This is rigid, and durable. Its disadvantage is that it is susceptible to ultra violet light radiation which causes the fibresto swell resulting in a decrease in light transmission

(ii) Double sheet of polythene film inflated with air This requires constant refilling of the air.

(iii) Poly carbonate materials

 

Are rigid but flexible enough to be used in a quonsetstyle green house. They are impact resistant.

(iv) Acrylic

 

These are the most current but very expensive. Their advantages are: high light transmission, high impact resistance and great strength.

Properties of good construction material:

 

  • Combustibility: Materials which are highly inflammable are not good for construction.

 

  • Durability: Should be long lasting.

 

  • Insulation: Refers to heat retention. This is relative to the number and thickness of layers used.
  • Maintenance cost: This should be affordable.

(b) Framing materials: .­These      include:

(i) Aluminium

 

This is the most economical material for constructing green house frames. It has the longest life span and allows for light reflection.

(ii) Steel

 

It is heavier than aluminium hence it requires additional support. It has to be painted or galvanized to resist high moisture conditions within the green house.

(iii) Wood

This can be used but its disadvantage is that it deteriorates fast. If wood is to be used, then treatment is necessary. However, avoid using pentachloride and creosote since they liberate fumes that are harmful to plants.

Uses of the green house

It is used for raising tender crops which are of high value but require a highly controlled environment for successful production e.g. flowers. The aim of using a green house is to reduce evapotranspiration by increasing the humidity and controlling the level of dryness.

Examples of crops grown in green houses are:

  • Flowers e.g. roses.
  • Peas,french beans, onions, vegetable, lettuce, conifers, melons, tomatoes.

 

#

Internet and Email Free Computer Studies Notes

INTERNET.

 

Why Study about the Internet?

 

  • To understand what the Internet is, the services that it offers, what is required in order to get connected, as well as to establish a connection and log out of the Internet.

 

What is the Internet?

 

  • It is a large no. of connected computers (or a large set of computer networks) linked together that communicate with each other, over telephone lines.

 

  • It is a worldwide computer network connecting thousands of computer networks, through a mixture of private & public data using the telephone lines.

 

  • It is a worldwide (global or an international) network of computers that provide a variety of resources and data to the people that use it.

 

  • Internet refers to a global inter-connection of computers and computer networks to facilitate global information transfer. It is an interconnection of computers throughout the world, using ordinary telecommunication lines and modems.

 

The Internet uses VSATS (Very Small Aperture Telecommunication Systems) such as Telephone lines, Satellite.

 

The other names for the Internet are:

 

  • The
  • Information Superhighway.
  • Cyber space.

 

Internet is a facility that links the Internet users to the actual Internet documents.  Therefore, it is a system that links together many kinds of information all over the world.  This technology allows computers equipped with telecommunication links to exchange information freely, and as such, the Internet has enhanced what is being referred to as a global village.

 

Internet enables companies, organizations, individuals, schools and governments to share information across the world.

 

A computer on the Internet can be located anywhere in the world.  The Internet enables the computer to communicate with any other computer.

 

HISTORY (DEVELOPMENT) OF THE INTERNET.

 

The Internet was started by the U.S Department of Defence in 1969 as a network of 4 computers called ARPANET.  Its aim was to connect a set of computers operated by several Universities and Scientists doing military research so as to enable them share research data.

 

The original network grew as more computers were added to it.  By 1974, 62 computers were already attached.

 

In 1983, the Internet split into 2 parts; one dedicated exclusively (solely/only) to military installations (called Milnet), and the other dedicated to university research (called the Internet), with around 1,000 host computers.

 

In 1985, the Canadian government developed the BITNET to link all the Canadian Universities, and also provided connections into the U.S Internet.

 

In 1986, the U.S National Service Foundation created NSFNET to connect leading U.S universities.  By the end of 1987, there were 10,000 host computers on the Internet and 1,000 on BITNET.

 

In 1987, the National Science Foundation leased (acquired/rent) high-speed circuits to build a new high-speed backbone for NSFNET.  In 1988, it connected 13 regional internal networks containing 170 LAN’s and 56,000 host computers.

The Canadian Research Council followed in 1989, replacing BITNET with a high-speed network called CA*net that used the Internet protocols.  By the end of 1989, there were almost 200,000 host computers on the combined U.S and Canadian Internet.

 

Similar initiatives (plans/projects) were undertaken by other countries in the world, such that by the early 1990s, most of the individual country networks were linked together into one worldwide network of networks.

Each of these individual country networks was different (i.e., each had its own name, access rules, and fees structure), but all the networks used the same standard as the U.S Internet network.  So, users could easily exchange messages with each other.

 

By 1990s, the differences among the networks in each of the countries had disappeared, and the U.S name; Internet began to be used to mean the entire worldwide system of networks that used the Internet TCP/IP protocols.

 

A Protocol – a set of rules and standards that computers use to communicate with each other over a Network.

 

Features of the Internet.

 

  • The Internet is a collection of networks; it is not owned or controlled by any single organization, and it has no formal management organization. However, there is an Internet Society that co-ordinates and sets standards for its use.

In addition, Networks have no political boundaries on the exchange of information.

 

  • Networks are connected by Gateways that effectively remove barriers so that one type of network can “talk” to a different type of network.

 

  • To join the Internet, an existing network will only be required to pay a small registration fee and agree to certain standards based on TCP/IP.

 

The costs are low, because the Internet owns nothing, and so it has no real costs to offset.  Each organization pays for its own network & its own telephone bills, but these costs usually exist independent of the Internet.

 

  • Networks that join the Internet must agree to move each other’s traffic (data) at no charge to the others, just as it is the case with mail delivered through the International Postal system. This is why all the data appear to move at the cost of a local telephone call, making the Net a very cheap communication media.

 

FUNCTIONS OF THE INTERNET.

 

The Internet carries many kinds of traffic, and provides users with several functions.  Some of the most important functions are:

 

 

Many people all over the world use the Internet to communicate with each other.

 

Internet communication capabilities include; E-mail, Usenet Newsgroups, Chatting and Telnet.  You can send e-mails to your friends anywhere in the world, chat with your friends, send instant messages, etc.

 

  1. Information retrieval.

 

The Internet is a library.  Thousands of books, magazines, newspapers and encyclopedias can be read on the Internet.

 

  1. Easy-to-use offerings of information and products.

 

You can find information for your school assignments, buy books online, check what the weather is like anywhere in the world, and much more.

 

 

 

INTERNET SERVICES.

 

The following are some of the services offered by Internet:

 

  • Electronic mail (e-mail).
  • Fax services.
  • Conference services.
  • Online chatting.
  • Downloading of programs.
  • Online shopping.
  • File transfer.
  • Entertainment (Games, Music and Movies).
  • Free information retrieval (e.g., Educational information).
  • Formation of Discussion groups, e.g. Usenet Newsgroups.
  • Video Conferencing.
  • Access & Use of other computers.

 

Electronic Mail (E-mail).

 

An E-mail is a system that enables sending & receiving of messages electronically through computers.  It is used for communication between organizations or departments in the same organization.

 

E-mail is a quick, cheap, efficient & convenient means of communication with both individuals and groups.  It is faster than ordinary mail, easy to manage, inexpensive and saves paper.

 

With Internet mail, it is possible to send and receive messages quickly from businesses, friends or family in another part of the world.  An E-mail message can travel around the world in minutes.

 

Fax services.

 

Fax services enable individuals & businesses to send faxes through e-mail at a lower cost compared to the usual international Fax charges.

 

Conference services.

 

Conferencing on the Web can be defined as the dynamic exchange of all kinds of information – text, graphics, audio, video, etc – in a situation whereby the conversations are organized by item and allows a participant to contribute spontaneous responses to any item in the conversation.

 

Application of Conferencing on the Web.

 

The conversation can:

 

  • Provide important information that can assist in decision-making.
  • Provide any required technical support.
  • Help in community-building, project management & distance learning.
  • Help to organize electronic meetings, etc.

 

The Internet also allows you to have access to various types of information you might require to make accurate and informed decisions, E.g., it provides information on business, education, sports, politics, etc.

 

Chatting.

 

Internet Relay Chat (IRC) is a chatting system on the Internet that allows a large no. of people from various locations of the world who are on the computer to chat (i.e., simultaneously hold live and interactive electronic conversations) among themselves.

 

You can join discussion groups on the Internet and meet people around the world with similar interests.  You can ask questions, discuss problems and read interesting stories.

 

Anyone interested in chatting can join a discussion forum on one of the listed topics.  Only people who happen to be signed on at the same time are able to talk because messages are not stored.

This discussion can be an effective business tool if people who can benefit from interactive conversation set a specific appointment to meet and talk on a particular topic.

 

Disadvantage.

 

  • Usually, the topic is open to all without security; so intruders can participate.

 

Information retrieval.

 

The Internet is a voluntarily decentralized network with no central listing of participants or sites.  Therefore, End-users, usually working from PCs are able to search & find information of interest located in different sites assisted by special software and data stored in readily usable formats.

 

The Internet gives you information on almost any subject.  This is because of the Worldwide Web (www).

 

The World Wide Web is a global (an international) system of connected Web pages containing information such as, text, pictures, sound and video.  The WWW is hypertext based (i.e., it is able to access text and graphical data formatted for easy search, retrieval and display).

 

With the WWW, you can review Newspapers, magazines, academic papers, etc.  In addition, Governments, colleges, universities, companies and individuals offer free information on the Internet.  E.g., you can inquire (find out) about universities in Britain or America.

 

Note.  Its major problem is finding what you need from among the many storehouses of data found in databases and libraries all over the world.

 

Dowloading of Programs.

 

There are thousands of programs available on the Internet.  These programs include; Word processors, Spreadsheets, Electronic cards, etc.

 

You can therefore, look for the latest software over the Internet, e.g., you can get the latest Anti-virus software, and in addition, retrieve a free trial issue.

 

Entertainment.

 

There are hundreds of simple games available on the Internet.  These include; Chess, Football, etc.  The Internet also allows you review current Movies and hear Television theme songs.

 

Online Shopping.

 

You can order goods and services on the Internet without leaving your desk.  E.g., you can view a catalogue of a certain clothes shop over the Internet and fill in an online Order form.

 

Commercial enterprises use the Web to provide information on demand for purposes of customer support, marketing and sales.

 

File Transfer.

 

Data in the form of files can be transferred across the Internet from one site to another using the File Transfer Protocol (FTP).  FTP software is needed at both ends to handle the transfer.  It is through FTP that the two pieces of software manage to ‘understand’ each other.

 

Discussion Groups.

 

A Discussion group is a collection of users who have joined together to discuss some topic.

 

There are many discussions on different topics including Cooking, Skydiving, Politics, Education, recreational, scientific research, etc.

 

Two of the commonly used discussion groups for business are;

  • Usenet newsgroups.
  • List Servers.

 

  • Usenet newsgroups.

 

These are the most formally organized of the discussion groups.

 

Using a facility on the Internet called USENET, individuals can gain access to a very wide variety of information topics.

 

Usenet Newsgroups are usually worldwide discussion groups in which people share information and ideas on a defined topic through large electronic Bulletin Boards where anyone can read any articles or write articles and post messages on the topic for others to see and respond to.

 

The individuals can add messages to different topics and read those contributed by others. For instance, users such as students can ask questions about problems they face, or they could contribute or give an advice on how to improve the teaching of the subject.

 

Messages can be easily linked so that it is easy to know messages that are related.

 

Establishing a new newsgroup requires a vote of all interested people on the Internet.  If enough people express interest, the new topic is established.

 

Note. To join a Newsgroup and be able to read messages on various topics, your computer must have Newsreader software such as Outlook Express, or Internet News.

Any Internet user can access some of these newsgroups, while other newsgroups will require to subscribe to a specific topic or set of topics.

Once you have subscribed, each time you access the newsgroups you are informed of any new messages added to the topics.  You can then read these messages and respond to them by adding your own message.

 

The Usenet software receives “postings” of information and transmits new postings to users who have registered their interest in receiving the information.  Each individual posting takes the form like that used for e-mail.

 

There are over 10,000 such newsgroups; however, each Usenet site is financed independently & controlled by a Site Administrator, who carries only those groups that he/she chooses.

 

  • List Server

 

A List Server (or list serve) group is similar to the Usenet newsgroups, but is generally less formal.

Anyone with the right e-mail server software can establish a list server, which is simply a mail list.

The processor of the List Server processes commands such as request to subscribe, unsubscribe, or to provide information about the list serve.  The List serve mailer directs messages to everyone on the mailing list.

To use a List server, you need to know the addresses of both the Processor and the Mailer.

To subscribe to a List server, you send an e-mail message to the List server processor, which adds your name to the list.  Many different commands can be sent to the List server processor to perform a variety of functions.  These commands are included as lines of text in the e-mail messages sent to the processor.

 

List servers are more focused that the Usenet newsgroups and have fewer members.  They are harder to find than the Usenet newsgroups because literally anyone can create one.

 

Video Conferencing.

 

Video conferencing provides real-time transmission of video & audio signals to enable people in 2 or more locations to have a meeting.

 

The fastest growing form of video conferencing is Desktop video conferencing.

Small cameras installed on top of each camera enable meetings to take place from individual offices.

Special application software (e.g., CUSeeMe) is installed on top of each client computer.  It transmits the image across a network to application software on a video-conferencing Server.  The server then sends the signals to the other client computers that are to participate in the video conference.  In some areas, the clients can communicate with each other without using the server.

Some systems have integrated other types of GroupWare with desktop video conferencing, enabling participants to communicate verbally to attend the same “meeting” while sitting at the computer in their offices.

 

Advantage of Video conferencing.

 

  • Saves time & cost, as it reduces the need to travel.

 

Access & Use of other computers.

 

The Internet has a facility called TELNET that enables a user on one computer to use another computer across the network, i.e., the user is able to run programs on the other machine as if he/she is a local user.

 

Telnet is a protocol, which enables a user on one computer to log in to another computer on the Internet.

 

TELNET establishes an error-free, rapid link between two computers, allowing a user to log on to his/her home computer from a remote computer even when traveling.  You can also log on to and use third-party computers that have been made available to the public.

 

TELNET will use the computer address you supply to locate the computer you want to reach and connect you to it.  You will, of course, have to log in & go through any security procedures you, your company, or the third-party computer owner have put in place to protect that computer.

 

Telnet requires an application image program on the Client computer and an application layer program on the Server of the host computer.  Many programs conform to the Telnet Standard (e.g., EWAN).

 

Once Telnet enables the connection from the Client to the Server, you can log in by use of commands.  The exact commands to gain access to these newsgroups vary from computer to computer.

 

Telnet enables you to connect to a remote computer without incurring long-distance telephone charges.

 

Telnet can be useful because, it enables you to access your Server or Host computer without sitting at its Keyboard.

 

Telnet can be faster or slower than a modem, depending on the amount of traffic on the Internet.

 

Note.  Telnet is insecure, because everyone on the Internet can attempt to log in your computer and use it as they wish.  One commonly used security precaution is to prohibit remote log ins via Tel-net unless a user specifically asks for his/her account to be authorized for it, or permit remote log ins only from a specific set of Internet addresses., e.g., the Web server at a university can be configured to only accept telnet log ins from computers located on the Kabete Campus network.

 

Electronic Commerce.

 

Many people are actively using the Internet for Electronic Commerce (i.e., doing business on the Internet).

The use of the Internet in E-commerce is not necessary for making money as such, but mainly to find information, improve communication and provide information.

 

Many people automatically focus on the retail aspect of e-commerce, i.e., selling products to individuals.  However, this is just one small part of e-commerce.  The fastest group and the largest segment of e-commerce is business-to-business settings.

 

There are 4 ways in which the Web can be used to support E-commerce;

 

  • Electronic Store.

 

Electronic Store is a Website that lists all the products or services a business wishes to sell, thus enabling customers to purchase them by using the Internet itself.

 

E-store sites provide physical goods and services.

 

The cost of providing information on the Web is low (unlike a Catalog, in which each page adds to the cost), and therefore, electronic stores can provide much information.  In addition, electronic stores can also add value by providing dynamic information.

 

E-mail can also serve the purpose of E-store.  This is because, e-mail is essentially a collection of e-stores.  The mail usually provides all the computer information needed for e-commerce, and advertises the mail to potential customers.  In return, the stores pay the mail a monthly fee or some percentage of sales.

 

  • Electronic Marketing.

 

E-marketing sites focus on the products or services of one company with aim of increasing sales.

This type of site supports the sales process, but does not make actual sales.  The goal is to attract and keep customers.

 

By doing so, such sites provide a wealth of information about the firms and products complete with technical details and photos.  Customers can review these but cannot buy over the Web.  The idea is to encourage the user to visit a local dealer, who will then make a sale.

 

Computers also use e-marketing sites to provide newsletters with information on the latest products and tips on how to use them.  Other companies enable potential customers to sign up for notification of new product releases.

 

E-marketing is cheaper in many ways than traditional marketing (radio, direct marketing, TV or print media).  This is because while it costs the same to develop these traditional media, it costs nothing to send information to the customers.  It is also easier to customize the presentation of information to a potential customer, because the Web is interactive.  In contrast, the other media are fixed once they are developed, and they provide the same marketing approach to all who use it.

 

  • Information / Entertainment provider.

 

The Information/Entertainment provider supplies information (in form of text or graphics) or entertainment.  These providers provide information from many sources with an aim of helping the users.

 

Several radio and TV stations are using the Web to provide broadcast of audio and video.  The Web also offers new forms of real entertainment e.g., enables new multiplayer interactive games, which are not available in any other media.  The information / entertainment providers generate revenue by selling advertisement printouts.

 

  • Customers Service sales.

 

This provides a variety of information for customers after they have purchased a product or service – to allow customers access most commonly needed information 24 hrs a day.

 

Many software companies post updates that fix problems so that customers can download for themselves.

Customer service sites benefit both the company and the customers.  They enable customers to get a 24 hr support and easy access to needed information.

 

They often reduce the no. of staff needed by automating routine information requests that previously had to be handled by an employee.

 

GroupWare.

 

GroupWare is a software that helps groups of people to work together more productively.

 

They are often organized using a two-by-two grid.

 

Same place Same time Different time
  Group support systems Group support systems
Different place Video teleconferencing, Desktop video teleconferencing E-mail, Discussion groups, Document-based GroupWare

GroupWare allows people in different places to communicate either at the same time (as on a telephone) or at different times.

GroupWare can also be used to improve communication and decision-making among those who work together in the same room, either at the same time or at different times.

GroupWare allows people to exchange ideas, debate issues, make decisions, and write reports, without actually having to meet face to face.  Even when groups meet in the same room at the same time, GroupWare can improve meetings.

The major advantage of GroupWare is its ability to help groups make faster decisions, particularly in situations where it is difficult for group members to meet in the same room at the same time.

 

The 3 most popular types of GroupWare are;

  • Discussion groups.
  • Group support systems.
  • Video Conferencing.

 

Group Support Systems (GSS).

 

Both e-mail and documents-based GroupWare are designed to support individuals and groups working in different places at different times.  They are not suited to support groups working together at the same time and in the same place.  In addition, they don’t provide advanced tools for helping groups to make decisions.

 

Group Support Systems (GSS) are software tools, designed to improve group’s decision-making.  GSS are used with special-purpose meeting rooms that provide each group member with a network computer plus a large screen video projection system that acts as electronic blackboards.  These rooms are equipped with special-purpose GSS software that enables participants to communicate, propose ideas, analyse options, evaluate alternatives, etc.  Typically, a meeting facilitator assists the group.

 

The group members can either discuss verbally or use computers to type ideas and information, which are then shared with all other group members via the network.  For large groups where only one person can speak at a time, typing ideas is faster than talking.  Everyone has the same opportunity to contribute and ideas can be collected much faster.  In addition, GSS enables users to make anonymous comments.  Without anonymity, certain participants may withhold ideas because they fear their ideas may not be well received.

The system also provides tools to support voting and ranking of alternatives, so that more structured decision-making process can be used.

 

Just like in document-based GroupWare, vendors use the Web browser as their client software.  So, almost anyone can access GroupWare Server.

 

Note. Discussion groups, document-based GroupWare and GSS all focus on the transmission of text and graphical images.

 

Information Superhighway.

 

A term coined by U.S Clinton administration referring to advanced information infrastructure accessible to individuals, groups and firms.

 

In general, the Information superhighway can be defined as;

 

  • A facility that provides a global electronic data interchange between computer users at a higher rate of message exchange, and at cheaper costs. g., the Internet that allows researchers, businesses, and electronic media to exchange information.

 

  • An Information Communication Technology (ICT) network, which delivers all kinds of electronic services – audio, video, text, and data to households and businesses.

 

The communication services on the superhighway can be one-to-one way (Telephones, e-mail, fax, etc); one-to-many (Broadcasting, interactive TV, video conferencing, etc), many-to-many (typified by bulletin boards and forums on the Internet).

Origin.

 

Information superhighway is a mass technology project aimed at creating a National Information Infrastructure (NII) in the U.S.

 

The concept emerged as the brainchild (idea) of U.S vice president Al Gore.   It is an alliance between the Federal government and a no. of industries.

 

The Information superhighway describes networks of Optic fiber and Coaxial cable linked by sophisticated switches that can deliver voice, data, image, text, and video signals all in the same digital language.

 

In the U.S, it has been proclaimed (declared) as the foundation for a national transformation to an information-based society, and a key element in the national efforts to sustain leadership in the world economy.

 

Governments and industries are developing a new method of competition, which will enable telecommunications, cable television, computer hardware and software companies, and entertainment corporations to work together to create and operate information superhighways.  These activities will finally result into a wide range of electronic services including electronic Shopping malls, collaborate electronic Education and distance learning, electronic Libraries, Multimedia information, messaging, and entertainment.

 

Web casting.

 

Web casting (or “Push technology”) is a special application of the Web that has the potential to dramatically change the way we use the Web /Internet.

 

With Web casting, the user signs up for a type of information on a set of channels.  Regularly (minutes, hours, days), the user browser contacts the Web server providing these channels to see if they have been updated.  If so, the browser will load the information, and if required by the user, will automatically display the information on the user screen.

 

Web casting changes the nature of the Web from one in which the user searches for information (a “pull” environment) into an environment in which the user accepts whatever information is on the Webcast Server (a “push” environment).   This is called the “Push” because the user does not request specific information, but rather permits the Web server to “push” the information when it becomes available.

 

The Web has been likened to a library because users move form site to site and page to page just like they move from shelf to shelf and book to book in a library.

 

Web casting is more like TV because the content and time of delivery is selected using the Web caster, the user only chooses the channels.

 

Web casting can be used for news (e.g., CNN) or financial reports (e.g., Stock market quotations), Corporate announcement, and as a replacement for broadcast e-mail.  It even has the potential to provide automatic updates to software packages.

 

Importance of services provided on the Internet.

 

The services offered by the Internet can be used as important tools in various ways:

 

  • As a research tool:

 

To learn about new developments or products, competitors, market news and customer opinions.

 

  • As an advertising / trading tool:

 

To help in selling goods or delivering information through the Web pages to customers on a 24-hour basis.

 

  • As a communication tool:

 

To support communication with customers, suppliers or staff through Electronic mail (e-mail).

 

  • As an Entertainment channel:

 

Most of the Games, Movies, and Television theme songs are available for free on the Internet.

In addition, you can have live, interactive conversations with people around the world including celebrities.

 

Users of the Internet.

 

Considering the facilities & the various tools offered, the Internet has attracted among others the following users;

 

  • Researchers can get information.
  • Writers and Scientists use the Internet to compile, compare and analyse their work.
  • Individuals use the Internet for their work or to communicate with each other.
  • People with the same interests can share ideas.
  • Large organizations use the Internet to communicate with each other, and also to keep in touch with subordinate (subsidiary) companies or their suppliers.
  • Students can communicate and gather information.
  • Business people can advertise, communicate and sell their goods.
  • Sales people use the Internet to keep in touch with their home offices.
  • Buyers can do their shopping online.

 

Exercise (a).

 

  1. (a). What do you understand by the term Internet?

(b). What are the other names of the Internet?

  1. Describe the Functions of the Internet.
  2. List 6 services that are offered on the Internet.
  3. Identify 6 categories of people who can benefit through the use of the Internet.

 

Exercise (b).

 

  1. Define the Internet.
  2. Briefly describe six services offered by the Internet.
  3. Discuss the growth of Internet in recent days.
  4. Explain the importance of Information superhighway (Internet).
  5. Write short notes on the following:
  • E-commerce.
  • Information Superhighway.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CONNECTING (LOGGING ON) TO THE INTERNET.

 

Log On -To identify yourself & gain access to a computer.  To log on, type a user name & a password.

 

Facilities Needed.

 

To use the Internet, you must have access to it.  In order to get connected to the Internet and access the World wide Web, you will require the following facilities:

 

  • A Computer.

 

The computer to be used must have the following desirable elements;

 

  • A Fast processor, e.g., Pentium 1 & above – to quickly access and download information & programs from the Internet.
  • RAM memory of 32 MB & Above.
  • Hard disk capacity of at least 400 MB.
  • A high-quality Colour Screen – to enable you view the various graphics and images.
  • Free disk space on which to download the information or programs from the Internet.

 

  • Web Browsers.

 

Web browsers are application programs that are used to retrieve Web pages from the Internet onto your Personal Computer.

 

One of the most popular Web browsers is Internet Explorer from Microsoft.

 

Each Web page in the World Wide Web is based on an HTML (HyperText Mark Language) file.  A Web browser decodes the information in an HTML file and displays a Web page on your computer screen according to its instructions.  This process is called Downloading.

 

  • Downloading is the process of copying files from one computer to another by using a Modem or a network connection. You can also download files from the Web to your hard disk.

 

  • HTML (Hypertext Markup Language) -The language used to create Web pages. To view HTML documents, use Web browsing Software.

 

  • Telephone lines.

 

  • Modem (Modulator/Demodulator).

 

On the Internet, computers exchange information through Telephone lines.  Therefore, to use the Internet, you need a Modem & a Telephone line.

 

A Modem is a device that enables you to connect to the Internet, and access information.

 

As a Transmitting modem, it translates computer information (which is in digital form) into analogue form (the form that can transmit over telephone lines).  This process is called Modulation.

As a Receiving modem, it translates the information back into digital form (a form that your computer can understand); a process called Demodulation.

 

The Modem must be fast.  This helps to reduce the amount of time spent waiting for Web pages, files, or messages from the Internet.

Modem speeds are expressed in Bits per second (bps).  The typical speeds are 9,600 bps, 4.4 Kbps (Kilobits per second), 28.8 Kbps, 56 Kbps, etc.

 

  • Internet Service Provider (ISP).

 

When connecting to the Internet using a modem, you need to sign up with an Internet Service Provider (ISP).

 

  • Internet Service Provider (ISP) is a commercial organization (or a company) that provides Internet connections, along with a set of support services usually for a fee. It maintains a Server that is directly connected to the Internet.

 

  • Internet Service Provider – A company or organization that provides Internet Access, usually for a fee. To connect to your ISP, use a modem.

 

Most people and organizations connect to the Internet over a Telephone line through an ISP.  However, some larger businesses and institutions (such as universities) have their own Internet connections.

 

An ISP usually has a no. of Host computers.  These host computers usually provide space for the storage of user’s electronic mail messages, storage of user’s Web sites and a set of related facilities such as, advice, support software and appropriate security.

 

Examples of the local ISPs include;

  • Africa Online, Kenya Web, ISP Kenya, Swift Kenya, and Inter-Connect.

 

Connecting to an ISP involves calling the provider and setting up a PPP account.  When you open an account with an ISP, you will be provided with a User name and a Password.

 

  • Username – Every time you get connected, you require a name to identify yourself on the Internet.

 

  • Password – This is needed for security purposes. It ensures that your Internet account is secure.

 

Note. ISPs charge for the services rendered.

  • Website.

 

This is an area in the Internet where information of a particular organization is kept.  The Website must be updated on daily basis.

 

Content Provider – A business that uses the Internet to supply you with information such as news, weather, business reports & entertainment.

 

ACCESSING THE INTERNET.

 

There are 3 common ways in which an individual user can access the Internet:

 

  • Through a connection already setup through the computer in your organization. Typically, the service is accessed in a similar way to other services on a LAN.

 

  • Through paying for an account with an Internet Service Provider (ISP).

 

In order to access an ISP directly, the user will need a Personal Computer, a Modem, a Telephone line & a suitable software in order to connect to the service.  Most ISPs give help and advice on how to connect.

 

  • Through a Bulletin Board Service (BBS), e.g. CompuServe. BBS are commercially run information providers, each with its own information services and normally offering access to Internet services.

The BBS companies normally sell some form of start-up package.

 

Setting up an Internet account.

 

Purpose.

 

  • To be able to gain access to the facilities that are offered on the Internet, the user needs to log on. To log on, use Dial-Up to connect to the Internet, and then use a Web browser like Internet Explorer to load Web pages.

 

There are several ways to start Internet Explorer;

 

Method 1.

 

  1. Double-click the Internet Explorer icon on the desktop.

 

Method 2.

 

  1. On the taskbar, click Start, point to Programs, then click Internet Explorer.

 

You may be required to make a connection through your ISP in order to log on to the Internet.  To do this, a Dial-up Connection dialog box is displayed.

 

  1. Click in the User name box, and type a user name, for instance ‘Iat’.
  2. Type in your password in the Password box, and then select the Save password

The password appears in asterisk format (***) for added privacy and security.

 

  1. Click the Connect button to access the Internet.

 

The Internet Connection wizard creates an Internet connection for you, and then displays a list of Internet Service Providers (ISPs) and information about their services.

To sign up for a new account, click an ISP in the list.

 

Wizard – A tool that walks you through the steps of a complex task.

 

Selecting options in the Internet Connection Wizard.

 

If you are connecting to the Internet using a modem & an Internet Service Provider (ISP), your ISP will supply most of the information needed.  You will also need to provide the following information.

 

 

Information                                                    Needed for.

 

The ISP you want to use                                 choosing an ISP

 

Your address & billing information              payment for your ISP account

 

Note. You may be prompted to restart your computer during the Internet connection process; save and close any open documents before you proceed.

 

  1. After successfully logging on, the Internet Explorer displays the “Home page” and a Connection Indicator icon on the taskbar to indicate that you are online.

 

Method 3. To open Internet Explorer from Outlook Express.

 

  1. On the Help menu, point to Microsoft on the Web, then click the Web option you want.

E.g., click Search the Web to look for a Web site, a person, a company, or an organization.

– Or-

Click Best of the Web to open the MSN.COM page that lists some of the best sites on the Web.

 

Online Service – An Internet service that provides a wide range of content to its subscribers including Internet Access.

 

Parts of the Microsoft Internet Explorer screen.

 

  • Title bar.
  • Menu bar.
  • Address Bar. It contains the Address box in which you type an address to open the file you want.  The Address Bar provides a method of opening files that are on the Internet or your computer.
  • Current page, with Links.
  • Scroll bars.
  • Status bar.
  • Standard toolbar; with buttons such as, Back, Forward, Stop, Refresh, Home, Search, Favorites, History, Mail, Print, Discuss.

You can use the toolbar buttons in the Internet Explorer to move between Web pages, to search the Internet or to refresh the content of Web pages.

 

Button                                           description.

Forward                                        moves to the next Web page.

Back                                             moves to a previously viewed Web page.

Home                                            jumps to your home page.

History                                         displays a list of recently visited sites.

Favorites                                      displays a list of Web pages that you have selected as your favorites.

Refresh                                         updates the contents of a currently displayed Web page or window.

Search                                          opens a Web page that lists the available search engines.

Edit                                               opens FrontPage Express or Windows Notepad so you can edit a Web page.

 

Print                                              prints a Web page.

Stop                                              stops the downloading of a Web page.

Mail                                              opens Outlook Express or Internet News.

 

Viewing connection information.

 

Purpose.

 

  • When you register with an ISP, you acquire an Internet account with them and from time to time, you may want to view connection information such as, how long you have been online, the speed of connection & the activities done during the online session.

 

  1. Right-click the Connection Indicator icon on the Taskbar.
  2. From the shortcut menu that appears, click Status.

The Connected to <Africa Online> dialog box appears:

 

Some of the useful information displayed on this window includes:

  • The speed at which you are connected, e.g. 26,400 bits per second (bps).
  • The duration you have been online, e.g., 2 minutes, 50 seconds.
  • The Transfer rate, in case you are downloading files from the Internet.

 

  1. Click OK, after viewing the details.

 

Customizing the Web browser.

 

Purpose.

 

  • Moving from site to site can be slow if the ISP or Internet lines are busy, if the Host server (the server storing the site you are trying to access) is busy, or if you are using a slow modem.

 

If a site contains graphics (or other multimedia content like video, audio, etc) you can prevent the graphics from downloading so as to speed up browsing.

 

  1. On the Tools menu, select Internet Options….
  2. Click the Advanced tab, then scroll down to the Multimedia
  3. Deselect the options or content that you want turned off, e.g., Show Pictures, play Animations, or Play Videos, then click OK.

 

Multimedia – A technology that combines data/text, voices/sounds, graphics, pictures, videos and images into one complete system.  Multimedia uses Optical disk, e.g., CD-ROM to stock all the above in one media.  Multimedia can be used in training.

 

 

 

 

 

Logging out from the Internet.

 

Purpose.

 

  • As long as you are connected to the Internet, you continue to incur Telephone and account usage charges. This can prove to be expensive in the long run.

 

It is recommended that you disconnect or log out from the Internet soon after you have finished with a session.  This is to avoid incurring extra or unnecessary charges.

 

  1. Right-click the Connection Indicator icon on the Taskbar.
  2. From the shortcut menu that appears, click Disconnect and you will automatically be logged out.

 

When you log out, the Connection Indicator icon is disabled.

Note. Some browsers or ISPs automatically disconnect you from the Internet when there is no activity between the user and ISP for a period of about 5 – 10 minutes.

 

Understanding the World Wide Web.

 

Purpose.

 

  • To understand some of the Internet terminologies like Web pages, Web sites, Web browsers, URLs and Home page.

 

The World Wide Web (www).

 

The World Wide Web is also known as the Web, WWW or W3.

 

  • The Web is an Internet application (software) that uses the Internet as its network.

 

  • World Wide Web is the graphical, multimedia portion of the Internet.

 

  • The WWW is a collection of hyperlinked Web pages published on the Internet.
  • The World Wide Web is a global (an international) system of connected Web pages containing information such as, text, pictures, sound and video. The WWW is hypertext based (i.e., it is able to access text & graphical data formatted for easy search, retrieval and display).

 

The Web is a part of the Internet.  It is comprised of millions of Web pages.  This huge collection of documents is stored on computers, called Hosts, around the world.

The documents may contain text, pictures, sound, small programs or forms to be completed by a user.

 

To view files on the Web, you need Web browsing Software.   This software can be used to view different locations on the Web or to explore the Web pages.

 

Web pages.

 

  • Web pages are documents published by organizations and individuals who are interested in putting themselves on the Web. Web pages can include text, pictures, sound and video.

 

  • Web page is a location on the WWW, usually a Web site.

 

The Web pages can also be found on company Intranets.

 

Intranets and Extranets.

 

What is an Intranet?

 

  • An Intranet is an internal corporate network used in organizations to enable the sharing of documents among coworkers. It supports users inside one organization (usually on a LAN).

 

  • Intranet – A private network within an organization. It can connect all types of computers within an organization.

 

Intranet has a private Web Server, which can be made available to the entire organization, individual department or to specific departmental workgroups.

 

An Intranet uses the infrastructure and standards of the Internet and can be connected to the Internet.

 

 

Note. Intranet applications are usually combined with the normal Web application of other organizations, but are hidden from those outside the organization.

 

Extranet:

 

An Extranet works in much the same manner as an Intranet, but provides information to selected users outside the organization.

E.g., a certain university can have an Internet library containing millions of articles, but only make it available to staff and students at colleges and universities within the country.

 

To access the library, you must provide a password when you connect to the Internet site.

 

Home Page.

 

  • Home page is the Web page loaded when Internet Explorer is first started, i.e., when you access the Web.

E.g., the Internet address of the Windows home page is http://www.Microsoft.com /Windows

 

  • Home page can also the first page of a company or an individual’s Website on the Web.

Those who offer information through the Web must first establish a Home page – a www text and graphical screen that welcomes the user and explains the organization that has established the page.

  • Home page – is the introductory page of a Web site. The home page contains links to other pages in the site.

 

Notes.

 

  • You can set any Web page as your Home page.
  • Do not confuse your home page with the home page of the Websites you visit. Your home page is set through Internet Explorer.  The home page of a Website is the introductory page for the site.

If you click a hyperlink such as Home on a Web page, you will jump to the home page of the Website, not yours.  To access your home page, click the Home button on the Explorer toolbar.

 

Web Site.

 

  • A collection of Web pages belonging to an organization or individual. These organizations or individuals maintain the Website.

 

  • Web site – A group of related Web pages.

 

  • A Web site is a screen or a collection of screens that provide information in text or graphical form that can be viewed by Internet users by activating the appropriate icon or commands.

 

Web Browsers (Web browsing software).

 

A Web browser is a program that lets the user browse through information on (or surf) the Web.

 

Information on the Web is structured into pages.  Each page has a specific address that is used to locate and access information on that page.

 

A WWW browser program enables the user to either search for data by name or by specifying locations known as Uniform Resource Location (URL).

 

The two common Web browsers are:

 

  • Internet Explorer from Microsoft.
  • Navigator from Netscape.

 

 

 

 

 

 

Browsing the Web.

 

This is also known as Navigating or ‘Surfing’ the Web.

 

  • To Browse is to navigate the Internet or the contents of your computer.

 

  • Browsing can also be defined as moving around and between Web pages.

 

Using a Web browsing software you can read documents, listen to music, watch videos, make purchases, participate in surveys, advertise products, do research, share interests and download files on the Web.

 

EXPLORING / BROWSING THE INTERNET.

 

Use the Internet Explorer on your Windows desktop to browse the Web.

 

There are several ways in which you can browse the Web pages or “surf the net”.

 

  • When viewing a Web page, you can navigate the Internet by clicking Links, Underlined text or special features that cause you to jump to another Web page.

 

Hyperlinks.

 

 

A Hyperlink is a coloured or underlined text or a graphic that you click to ‘jump’ from one location to another.  The hyperlinks enable the user to ‘jump’ to another file, or to another location in the same file.

 

All Web pages have hyperlinks.  These links:

 

  • Connect one part of a Web page to another part of the same Web page. This is useful if the Web page is large.
  • Connect one Web page to another Website somewhere on the Web.
  • Connect a page to a file, such as a sound clip, video, a Spreadsheet or a Word document.

 

The links can connect to objects stored anywhere on the Internet.

 

Hypertext links are indicated by underlined text highlighted usually in blue.  Hyperlinks can also be represented by buttons, graphics or pictures.

 

To find hyperlinks on a page, move your mouse pointer over the page and where there is a hyperlink, the mouse pointer will change into a hand with a pointing finger.  When you click a link, another Web page appears.

 

As you browse the Web, Internet Explorer stores the sites and pages that you visit.  Usually, the hyperlinks you previously selected are colored differently.  Internet Explorer does this to remind you that you have already visited the page identified by this link.

 

  • You can also use the Standard toolbar buttons in the Internet Explorer to move between Web pages, or to search the Internet.

 

History.

 

Internet Explorer remembers the Websites and Web pages that you have visited.  It keeps record of each Web page as it is downloaded.  This is the History feature.

 

You can therefore, easily return to the page you have visited.  To redisplay the page you have just left, click on the Back button.  To move to the next page (available only if you have moved back), click the Forward button.

 

Web Hosting.

 

A World Wide Web Server is a computer with programs that answer requests for documents from Clients (browsers) over the Internet.  Files containing Web sites are placed on these servers.

 

A Host computer is any computer connected to the Internet and stores information that has been made available to the Web.

 

ISPs also use host computers to store user’s electronic mail messages, Web sites and other related facilities such as, support software and appropriate security.

 

Web Address (Uniform Resource Locator – URL).

 

An Address is the location of a file.

 

Each Web page in the world has a unique Internet address or location.  Internet addresses are also called the Uniform Resource Locator (URL).  E.g., the general URL for Microsoft is http://www.Microsoft.com./

 

You can use addresses to find files on the Internet & your computer.  You can instantly display any Web page if you know its URL.  E.g., http://www.compaq.com. 

 

AutoComplete – A feature in the Address Bar.  When you begin typing a previously used address, this feature finishes it as you type.

 

How the Web Works.

Each Client computer needs an application software package called a Web browser, such as Navigator, Internet Explorer.

Each Server on the network needs an application software package called a Web Server.  There are many different Web servers, such as those produced by Netscape, Microsoft and Apache.

 

In order to get a page from the Web, the user must type the Uniform Resource Locator (URL) for the desired page, or click on a link that provides the URL.  The URL specifies the Internet address of the Web Server, the directory and the name of the specific page required.  If no directory or page is specified, the Web server will display whatever page has been defined as its Home page.  If no server name is specified, the Web browser will assume that the address is on the same server and directory as the last request.

 

In order for the Web server to understand requests from the Web browser, they must use the same standard protocol.  If there was no standard, then each Web browser would use a different way to request pages.  This means that, it would be impossible for a Web browser from Netscape to communicate with a Web server from Microsoft.

The standard protocol for communication between a Web browser and a Web server is the HyperText Transfer Protocol (HTTP).  An HTTP request for a Web browser to a Web server has 3 parts, but only the 1st part is required, the other two are optional.

 

  • The Request Line, which starts with a command (e.g., GET), provides the URL, and ends with HTTP version number that the browser understands.

 

  • The Request Header, which contains a variety of optional information such as the Web browser being used (e.g., Internet Explorer), the date, the User ID and Password for using the Web pages as password protected.

 

  • The Request Body, which contains information sent to the Server, such as information from a firm.

 

Note.  Every Web user must provide the Internet address of the receiving computer, otherwise, the server would not know where to send the requested page.

Some browsers also provide the requestor’s e-mail addresses as well.  Most Web servers keep a record of Internet addresses of all the requests (and the e-mail address, if provided by the browser).  Some companies use this information to make a follow up with prospective customers.

 

An HTTP response for a Web server to a Web browser also has 3 parts, but only the last part is required, the first two are optional.

 

  • The Response Status, which contains the HTTP version number the server has used as status code (e.g., 200 means ‘OK’, 404 means ‘Page not found’), and reason phrase (i.e., a text description of the status code).

 

  • The Response Header, which contains a variety of optional information such as the Web server being used, the date, the exact URL of the page in the response body, and the format of the body (e.g., HTML).

 

  • The Response Body, which is the Web page itself.

 

Internet Addresses.

 

Internet addresses are strictly regulated, otherwise, someone could add a computer to the Internet that had the same address as another computer.

 

Each address has 2 parts; The computer name and its domain.

 

The Domain is the specific part of the Internet to which the computer is connected (e.g., Canada, Australia, etc).

 

The general format of an Internet address is therefore: computer.domain.  Some computer names have several parts separated by periods.  For example, the main university Web server of an imaginary University like Yairobi can be www.Yairobi.edu, while the college of Humanities and Social Sciences server can be www.chss.Yairobi.edu.

 

Each domain has an address board that assigns address for its domain.  The boards ensure that there are no duplicates.

 

Finding Web pages (information) on the Web.

 

There are 3 ways you can use to find interesting and useful Web pages on the Web;

 

  • You could get the Web address from an advertisement.

 

Many businesses include their Web addresses in their Television and Print advertisements.

 

  • You click a link that will enable you jump from one page to another.

 

Many industries or organizations, magazines and topic experts maintain pages that provide links from page to page.

 

  • Use of Search Engines.

 

Search Engines / Search Services.

 

  • A Search engine is software that helps in locating information in the Web.

 

  • Search engine is a tool that searches the Web for information that you want to find.

 

Purpose.

 

  • If you want to get some information concerning an area or subject of interest over the Web but you do not know where to find it, you can use a Search engine to locate sites that contain the information.

 

  • Locate particular information in a Website, e.g., if you wish to read the Sports news you can load a Web site like http://www.cnn.com/, and then use a search engine within that site to locate information on Sports.

 

The following are the various search engines:

 

 

These search engines offer different kinds of searching capabilities.  However, they differ in the way they organize information in response to your request.

 

Yahoo focuses on the largest & most important Websites and organizes them in a directory format.  Small and little known Websites are excluded.  Therefore, if you are looking for the address of a well-known company or product or a popular topic, Yahoo is probably the easiest way to find it.

 

Alta Vista is the broadest of all.  It lists almost everything it can find.  It is probably the best choice if you are looking for an unclear topic or a very specific combination of topics or words (e.g., to find a famous quote).

 

The major disadvantage of Alta Vista is that, you may have to look through dozens of sites before you find the ones you want.  In addition, Alta Vista does not provide some help in focusing your search.

 

Excite is easier to use in that, it uses advanced special intelligence techniques to help you search those pages that best match your interest.  E.g., after looking at the result of a search, you can tell Excite to find more pages that are similar to a specific page it has found.  Excite will then search again and present those pages first.  In this case, Excite refines the search based on the characterization of the page you have selected.

 

Meta Crawler provides the best search facilities.  It does not search the Web and provide a list of what it finds.  Instead, whenever you enter a search request, it simultaneously sends that request to several search engines (including Yahoo & Alta Vista), then combines, and organizes the information it receives from all the search engines into one display.

 

How Search Engines find Web pages.

 

Hundreds of thousands of new Web pages are created each day.

 

There are 2 ways that search engines use to locate Web pages:

 

  • Use of Spiders / Robots.
  • Through Submissions.

 

 

Search Engines normally use software spiders to explore the Web.  The Spiders are usually automated robots that travel around the Web looking for new pages, and creating links to them.

 

These spiders methodically search all the pages on the Websites they can find and report back their discoveries.  The search engine builds an index to these pages based on the words they contain.  When you connect to a search engine, and type a few words describing what you want, the Search engine will search its index for these keywords and provide you with a list of pages that contain them.

 

 

These are derived from people who have created new Web pages and then submit information about the pages they have created.

 

  1. Select a search engine, e.g., Yahoo, and type its address in the Address box, i.e., http://www.yahoo.com/.

 

Once the search engine home page appears, type a keyword or phrase in the Search box, e.g., Kenya, then click the Search button.

 

Note.  The steps may vary depending on the search engine you are using.

 

  1. When the search is completed, a list of sites that contain the keyword or phrase you are looking for is displayed. Select a site whose description comes closest to the information you desire and click on its link.
  2. If there are many sites, an option that allows you to view the next 10 or so matches is displayed. Click on this if necessary to view the next set of links.

If there are too many matches, you may want to use an additional keyword to narrow down the search.  E.g., to find the sites that contain information about the economy in Kenya, in the Search box, type phrase “Kenya AND Economy”.

  1. Click the Search
  2. From the search results, select the links that may help you get the information you require.

 

Locate information within a Website.

 

Once you access a Website, you can search for specific text or information on that site or page.

 

Unlike search engines like Yahoo, Infoseek, Lycos, Web Crawler, and Excite that present you with the URLs or links of sites that hold information you are looking for, search engines within a Web page locate information within that Web page.

 

  1. Load the Web page to browse. g., let’s use a Website: http://www.carleton.ca.
  2. Click in the Search box, and type a keyword(s), e.g., International AND Student.

 

Note. When typing in a keyword, you can use logical words or operators like AND (when you want to display results that meet both criteria) and OR (when you want to display results that meet one of the two criteria).

  1. Click the Search button, to begin the search.
  2. From the Search Results screen, click on a link that is closest to your requirements.

 

To open a favorite Web site from the Start menu.

 

  1. Click the Start button, point to Favorites, and then click the Web page you want.

 

To search the Web from the Start menu.

 

  1. Click the Start button, point to Find, then click On the Internet.

To use the Run command to open a Web page.

 

  1. Click Start, click Run, and then type the Internet address you want.

If the page you are opening is one you’ve viewed before, the AutoComplete feature can complete the address for you.

To find pages you’ve recently visited.

 

To find Web sites and pages you’ve viewed in the last few days, hours, or minutes.

 

 

  1. On the toolbar, click the History

The History bar appears, containing links for Web sites and pages visited in previous days and weeks.

  1. In the History bar, click a week or day, click a Web site folder to display individual pages, and then click the page icon to display the Web page.

 

Notes.

  • To return to the last page you viewed, click the Back button on the toolbar.
  • To view one of the last nine pages you visited in this session, click the arrow to the side of the Back or Forward button, and then click the page you want from the list.

 

 

 

 

To enter Web information more easily.

 

The AutoComplete feature saves previous entries you have made for Web addresses, forms, and passwords.

When you type information in one of these fields, AutoComplete suggests possible matches.

 

  1. When typing an information in the Address bar, and the AutoComplete feature suggests what you want to enter in that field, click the suggestion. If not, continue typing.

 

Setting or changing a Home Page.

 

Home page is the page that is displayed every time you start Internet Explorer.

 

Note.  Make sure it is a page that you want to view frequently, or make it one that you can customize to get quick access to all the information you want, such as the Msn.com home page.

 

Purpose.

 

  • To enable the user to choose or specify a page that will provide a good starting point for exploring the Web.

The Home page will appear each time the user accesses the Web.

 

  1. Go to the page you want set as your Home page.
  2. On the Tools menu, click Internet Options….

The Internet Options dialog box appears.

  1. Click the General
  2. Under the Home Page section, type the address of the new home page in the Address box. Alternatively, click Use Current to make the current Website the home page.
  3. Click the OK

 

Tips.

 

  • To restore your original home page, click Use Default.
  • You can return to your home page anytime by clicking the Home

 

Exercise.

 

  1. Mention at least 4 facilities that are needed to connect to the Internet.
  2. How can you establish the time you have been online in a session?
  3. In a step-by-step format, illustrate how you can log out of the Internet.
  4. Define the following terms:
    • Worldwide Web.
  5. (i). What is a Web site?

(ii). Give the advantages and disadvantages of a Web site.

  1. Give 2 examples of Web Browsers.
  2. Explain the term ‘Host computer’.
  3. Define the word ‘History’ with reference to a Web browser.
  4. (a). What is a Search engine?

(b). Give examples of Search engines.

  1. How does the Web work? Explain with the help of a diagram.
  2. Describe the procedure of finding information on the Web.

 

Downloading Web pages and programs from the Internet.

 

Purpose.

 

  • To enable the user to view Web pages without being connected to the Internet.
  • To be able to browse a site in a location that does not provide any network access.
  • In order to free your telephone lines.

Downloading a Web page.

 

  1. Load the Web page you want to download, e.g., http://www.nationaudio.com.
  2. Access all the links that you would like to read offline. Make sure that the whole Web page is fully loaded before moving to the next one.
  3. On the Favorites menu, click Add to Favorites.
  4. Select the option Yes, notify me of updates and download the page for offline viewing.
  5. Click OK, and then Logoff.

 

Downloading a program.

 

  • Programmers and software houses like Microsoft usually develop programs and may decide to send a test copy to their existing clients or to publish it on the Internet for interested users to test it for a specified period of time.

 

To test such software, a user will have to download the program onto the hard disk.  A user can also download a movie clip or games, etc, and view it offline to save on costs.

 

  1. Locate a site from which you wish to download a program, e.g., http://softwarenow.iboost.com.
  2. Select the category of programs you want to download, e.g., Games.
  3. Select a game category, e.g., Racing Games.
  4. Select a game you want to download.

 

Note. The window lists the properties of the program, e.g., version, file size.  Ensure that you understand the licence agreement, i.e., whether the program is freeware or shareware.

Freeware is a program that is absolutely free, while Shareware program is available for a limited period of time.

 

  1. To download the program, click on the download link, e.g., Download Cars & Brix.
  2. From the File Download dialog box, select Save this program to disk option, then click OK.
  3. In the Save As dialog box, select the folder in which you wish to store the downloaded program, then click Save.

 

Once the program is loaded, you can access the folder it was saved in and load it without being connected to the Internet.

 

Saving pictures or text from a Web page.

 

Purpose.

 

  • You can save information for future reference or in order to share with other people. You can save the entire Web page or any part of it: text, graphics, or links.

 

  • You can print Web pages for people who don’t have access to the Web or a computer.

 

To copy information from a Web page into a document,

 

  1. Select the information you want to copy, on the Edit menu, click Copy.

 

To use a Web page image as desktop wallpaper.

 

  1. Right-click the image on the Web page, then click Set as Wallpaper.

 

 

 

 

Saving information (a Web page) from the Internet to the Hard disk.

 

Purpose.

 

  • When you come across a Web page you would want to read, but it is too long, you can save the Web page onto your hard disk so as to read it later on when you are off-line. This helps in reducing the costs of browsing while online.

 

  1. Load the Web page you want to download.

Make sure the Web page you want to save is completely transferred to the screen of your Web browser.

  1. On the File menu, select Save As.
  2. In the Save HTML Document dialog box that appears, select the drive & folder where you want to save the page in.
  3. In the File name box, type a name for the page.
  4. In the Save as type box, select a file type.
  • To save all of the files needed to display this page, including graphics, frames, and style sheets, click Web Page, complete. This saves each file in its original format.

 

  • To save just the current HTML page, click Web Page, HTML only. This will save the information on the Web page, but it does not save the graphics, sounds, or other files.

 

  • To save just the text from the current Web page, click Text Only. This saves the information on the Web page in straight text format.
  1. Click Save.

The Explorer program automatically assigns the extension .htm to the file name.

 

To open a saved file.

 

  • After saving a Web page, you may want to read and analyze the information at a later time.

 

  • You may also want to send the saved file to another person via e-mail as an attachment.

 

  1. On the File menu, select Open. This displays the Open dialog box.
  2. Click on the Browse button in order to locate the folder where the file is stored.
  3. Click the file, then choose Open.

 

Note.  When you save a file in a local disk, only the text on the page is shown.  The graphics in a site are displayed in graphics placeholders (which appear as small rectangles).

 

Graphics and Download time.

 

When designing Web pages, graphics have to be incorporated sensibly into the Web page.

 

Although they are appealing to the eye, the more graphics you use on a Web page, the longer the Web browser will take to download the page.

 

File Formats.

 

The most common file formats found on the Internet are:

 

  • Graphic Interchange Format (GIF), and
  • Joint Photographic Experts Group (Jpeg).

 

Generally, GIFs are used for simple page design elements like lines, buttons and dividers, while JPEGs are mostly used for complex photographs and images.

 

Movie (video) files usually have the extension .avi, .mpg, or .mov, while Sound (audio) files have the extension .au, or .ra, or .ram, or .wav.

 

 

 

 

 

 

 

 

 

Printing Web pages.

 

Purpose.

 

  • To obtain a hard copy of the information that you have researched on and collected, for the purposes of reviewing later or filing.

 

Change how a page looks when it prints.

 

Before printing a Web page, it is advisable to check the settings in the Page Setup dialog box.

 

This will ensure that the right Paper size, Margins and Orientation of the page are set correctly.  You can also add headers and footers to a Web page.

 

  1. On the File menu, click Page Setup.
  2. In the Margins boxes, type the margin measurements (in inches).
  3. In the Orientation area, click either Portrait or Landscape to specify whether you want the page printed vertically or horizontally.
  4. In the Header and Footer boxes, specify the information to be printed, then click OK.

 

Printing the Web page.

 

  1. On the File menu, click Print to display the Print dialog box.
  2. Set the printing options you want, then click OK.

 

Exercise.

 

  1. What are the benefits of saving information from the Internet to your hard disk?
  2. List the type of files that can be downloaded from a Website.
  3. In which dialog box would one enter a footer and header of a Web page to be printed.
  4. Graphic objects are visible upon opening of saved Web pages. True/False? Explain.
  5. Define the following terms with respect to the Internet:
    • Access Provider. (6 marks).

 

Creating a Bookmark.

 

Purpose.

 

  • When you browse the Web, you may come across sites that you want to visit regularly.

Examples of such sites include; news sites like CNN or BBC.  You can decide to ‘bookmark’ the Web page.

 

The Bookmark feature (also known as a Hotlist or Favorites feature) allows you to store the addresses of Web pages that you frequently visit.  Hence, you do not have to constantly retype your favourite Web page addresses.  When you want to visit the site, simply select the bookmark from a list.

 

  1. Open the Website that you want to create a shortcut to. g., http://www.cnn.com.
  2. On the Favorites menu, choose Add to Favorites.

The Add to Favorites dialog box appears.  The name of the site you are in appears on the Name box.

  1. Under Create in: click the folder you want to add the site to, e.g., Links, then click OK.

This will add the title of the Web page in the Favorites list.

 

To go to a site using a Bookmark.

 

  1. On the menu bar, select Favorites.
  2. Select the folder that holds the favorites item, e.g., Links.
  3. From the drop-down list, click com.

 

To delete a Bookmark.

 

  1. On the menu bar, select Favorites.
  2. Point to the item from the Favorites list, e.g., CNN.com.
  3. Right-click the item, and then click Delete.

The Confirm File Delete dialog box appears.

  1. Click Yes, to remove the item from the list.

 

Working Offline.

 

Connection to the Internet usually means that you are using telephone lines, and therefore incurring telephone charges and usage on your ISP account.

 

Offline – Not connected to a network or the Internet.

 

BROWSING THE WEB (INTERNET) OFFLINE.

 

Purpose.

 

  • To enable the user to save on the time spent connected to the Internet, and hence reduce the general costs of being online.

 

  1. Access the Web site that you want to browse offline.
  2. Access all the links to download all the information you require.

Ensure that each Web page is downloaded completely before going to the next one.

  1. On the Taskbar, right-click the Connection Indicator button, then choose Disconnect.

 

The Connection Indicator disappears from the Taskbar showing that you are now working offline.

 

After disconnecting the user can go ahead and read all the downloaded information.  The user can also “browse” through the site while offline provided all the pages and links are downloaded.

 

Note. Some services like Internet, Usenet, Newsroom, or Shopping will not be available when you are offline.  To use these services, you need to re-establish the connection.

 

Making Web pages available for offline viewing.

 

Offline Reading –To view a Web page without being connected to the Internet.

You can download the page to your hard disk, disconnect from a network or the Internet, and read the material later.

 

When you make a Web page available offline, you can read its content when your computer is not connected to the Internet.

E.g., you can view Web pages on your Laptop computer when you don’t have a network or Internet connection.

 

  1. On the Favorites menu, click Add to Favorites.
  2. Select the Make available offline
  3. To specify a schedule for updating that page, and how much content to download, click Customize.
  4. Follow the instructions on your screen.

Note. Before you go offline, make sure you update your pages.  To do this, click the Tools menu, then click Synchronize.

 

To make an existing favorite item available offline.

 

  1. On the Favorites menu, click Organize Favorites.
  2. Click the page you want to make available offline.
  3. Select the Make available offline
  4. To specify a schedule for updating that page, and how much content to download, click Properties.

 

Get Help with Internet Explorer.

 

Purpose.

 

  • While working with Internet Explorer, you may sometimes need help on how to perform certain tasks or help on a particular topic of interest.

 

  1. On the Help menu, select Contents and Index (or press F1).

The Internet Explorer Help window is displayed.

  1. Click the Contents
  2. Click a book in the list, and then click a Help topic you want to look at.

The Help topic contents are displayed on the right-hand side of the Help window.

  1. Read the help and click the hyperlinks (blue, underlined text) if you want to see help on related topics.
  2. When you have finished, click the Close button to exit help.

 

Using the Index to get Help.

 

  1. On the Help window, click the Index
  2. Type in the first few letters of the word or topic that you are looking for.

In the Index box, all the help topics are listed in alphabetical order.

  1. Click the Display button to view the information about the topic selected.

 

Exercise.

 

  1. What is a Bookmark?

 

Advantages of the Internet.

 

  • One can download (copy) information from a Website.
  • The Internet has enabled the interlinking of people worldwide / globally.
  • It is convenient in the sense that you can access data 24 Hrs.
  • It is cheap, i.e., the operational cost that one may incur is low.
  • It has brought in the technology of doing the following; E-learning, E-Agriculture, E-commerce, E-governance, etc.
  • Provides up-to-date information.
  • It doesn’t require a lot of training to browse.
  • It provides entertainment facilities.
  • Can be used for research.
  • Brings harmony in the world, because people can communicate and exchange ideas.
  • The Internet can be accessed at any part of the world.
  • There is always a full backup provided by the Servers, hence no data loss.
  • It’s a fast way of communicating.
  • It provides an easy way to use offers in Information and products.

 

Internet provides information from almost all parts of the world that you need in order to make accurate and informed decisions.

You will get information you need from business to education, from sports to politics, from arts to eating out.

 

Disadvantages of Internet.

 

  • It’s a technology, which is fetched for (imposed/forced on) the Third world countries.
  • The cost of the Internet Service Provider is high.
  • It is leading to exposure of morally harmful shows such as Pornography.
  • It leads to spread of viruses.
  • Has proved to be unreliable especially accessing information.
  • No copyright rules meant to protect the property of an organization.

 

ELECTRONIC MAIL (E-MAIL).

 

About e-mail.

 

Electronic mail (also known as e-mail) is one of the common services provided by the Internet.

 

  • E-Mail is a worldwide system for sending & receiving electronic messages from one computer to another.

 

  • E-Mail (Electronic mail) refers to electronic messages sent over the Internet or a network. E-mail can contain both text & files.

 

With e-mail, users can create and send messages to one user, several users, or all the users on a distribution list.

 

Most e-mail software enable users to send text messages. In addition, users can attach files from Word processors, Spreadsheets, Reports, production data, etc, and then send them by e-mail.

 

Most E-mail packages allow you to do the same things you do with regular paper mail.  You can file messages in electronic file cabinets, forward copies of messages to other users, send “carbon copies” of messages, and so on.  The E-mail packages also allow you to filter or organize messages by priority.  E.g., all messages from a particular user (e.g., your boss) could be given top priority, so that they always appear at the top of your list of messages.

 

However, E-mail is a much faster, economical & convenient way of sending messages to family, friends and colleagues than the paper mail (usually called “Snail mail”).  Messages can be sent or received 24-hrs a day.  With “Snail mail” a message or a letter is sent to the recipient through the Post office and takes days or weeks before reaching the destination.

 

Components required.

 

For one to be able to communicate using e-mail, the following components are needed:

 

  • A Computer – where you will send or receive the e-mail messages.
  • An E-mail program.

 

Your computer must be installed with an e-mail program that lets you send, receive and manage your e-mail messages.

 

Examples of E-mail programs;

 

  • Microsoft Outlook, Outlook Express, & Microsoft Exchange from Microsoft.
  • Communicator from Netscape.
  • Lotus Notes.

 

  • E-mail address of the sender & the address of the receiver.

 

 

  • An Internet Service Provider (ISP) – company who will deliver your message to the receiver.

 

Once you send a letter or a message, it travels from your computer through a Modem, which connects your computer to the Internet using the Telephone network.  The Mail passes through various computers, until it reaches the final destination.

 

 

 

 

 

 

 

 

 

 

 

 

How E-mail Works.

 

The figure below shows how an e-mail message can travel over a Wide Area Network (WAN) such as the Internet.

 

 

Each Client computer in the Local Area Network (LAN) runs an e-mail software package called User Agent, e.g., Eudora, Lotus Notes, Outlook Express, Microsoft Outlook, etc.

 

The user writes the e-mail messages using one of the User Agents, which formats the message into 2 parts;

 

  • The Header, which lists the source and destination e-mail addresses.
  • The Body, which is the message itself.

 

The User agent sends the message header & body to a Mail Server that runs a special application package called a Message Mail Transfer Agent.  The Message Mail Transfer Agent in the Mail Server reads the envelope & then sends the message through the network (possibly through dozens of Message Transfer Agents) until the message arrives at the Mail Server of the receiver.

The Message Transfer Agent on this server then stores the message in the receiver’s mailbox on the server.

 

When the receiver accesses his/her e-mail, the User Agent on the receiver’s Client computer contacts the Message Transfer Agent on the Mail Server, and asks for the contents of the user’s mailbox.  The Message Transfer Agent sends the e-mail message to the client computer, which the user reads using the user agent.

 

E-MAIL STANDARDS.

 

Several standards have been developed to ensure the compatibility between different e-mail software packages.

 

The 3 commonly used standards are:

 

  • Simple Mail Transfer Protocol (SMTP).
  • X-400.
  • Common Messaging Calls (CMC).

 

All the 3 e-mail standards work in the same basic fashion.

Simple Mail Transfer Protocol (SMTP).

 

SMTP is the most commonly e-mail standard used on the Internet.

 

SMTP defines how Message Transfer Agents operate and how they format messages sent to them.  As the name suggests, SMTP is a simple standard that permits only the transfer of text messages.  Non-text files such as graphics or Word processing documents are not permitted.

 

However, several standards for non-text files have been developed that can operate together with SMTP.  They include; Multi-Purpose Internet Mail Extension (MIME), Unencoded & Bin Hex.

 

A different standard called Post Office Protocol (POP) defines how User agents operate and how messages to & from the Mail Transfer Agents are formatted.

 

POP is gradually being replaced by a newer standard called Internet Mail Access Protocol (IMAP).

The main difference between POP & IMAP is that, before a user can read a mail message with a POP user agent; the e-mail message must be copied to the client’s hard disk and deleted from the mail server.  With IMAP, e-mail messages can remain stored on the mail server after they have been read.  Therefore, IMAP is beneficial to users who read their e-mail from many different computers (e.g., at home, in office & in computer labs), because all e-mail is stored on the server until it is deleted.

 

X-400

 

The X-400 e-mail standard was developed in 1984.  It is a set of seven (7) standards that define how e-mail is to be processed by the User agents and the Mail Transfer Agents.

 

Common Messaging Calls (CMC).

 

The CMC standard is a simpler version of the X-400 standard.

It was developed in 1994.

It is more popular than X-400, because it is simple & it is also supported by a large no. of leading vendors/sellers.

 

File Transfer Protocol (FTP).

 

FTP enables you to send and receive files over the Internet.  FTP requires an application program on the client server and an application program on the FTP Server.  Many application packages use the FTP standard (e.g., WS-FTP).

 

Almost anyone can establish a FTP server, which permits anyone on the Internet to log in, send and receive files.

 

There are 2 types of FTP sites;

 

Closed FTP site.

 

A Closed site requires users to have permission before they can connect and gain access to the files.  Access is granted after the user provides an Account name with a secret password.

For example, a Network Manager would write a Web page using software on his/her client computer and their user FTP to send it to a specific account on the Web Server.

 

Anonymous FTP site.

 

Anonymous is the most common type of an FTP site.

It permits any Internet user to log in using the account of anonymous.

 

When using the anonymous FTP, you will still be asked for a password.  You can enter your Internet e-mail address as the password.

 

Many files and documents available via FTP have been compressed to reduce the amount of disk space they require.

Note.  If a file that you want has been compressed by a compression program that is not in your computer, you cannot access the file until you get the decompression program it used.

 

Using Lotus Notes.

 

One of the problems with e-mail is that, it lacks a structured way to support an ongoing discussion.  Each mail message is a separate item, unrelated to the other messages.  Usually, you can group and file e-mail messages into separate file folders, but it not possible to combine them.

 

Using Lotus Notes (a document database of text and graphics), documents with different sections can be organized into a hierarchical structure of sections, documents and folders.

 

Lotus Notes can be used as a computer Bulletin board to support ongoing discussions. Several topics and sub-topics can be created, and everyone or selected individuals in the organization can be given access.

 

Lotus Notes can also be used to organize a discussion among certain people such as a Project team working to improve manufacturing quality.  It might reduce the amount of time the team spent in face-to-face meetings, because many of the issues might be discussed before the meeting actually starts.

 

Lotus Notes also could be used to replace standard Word processors in preparing reports.  Each team member could use Lotus Notes to write a portion of report, which could then be passed to other team members for editing or comments.

 

Lotus Notes can also automate certain document-based processes (called Workflow automation).  For example, insurance claims require people from several different parts of an Insurance company to work together to process the claim.  One person might handle the initial claim, which would then be passed to an Insurance adjuster to finish a report.  Another person would process the payment.  All this paperwork could be replaced if Lotus Notes were used to prepare and pass the documents from one person to another.

 

Note. Lotus Notes has the ability to replicate.  Replication is the automatic sharing of information among servers when information changes.  E.g., Lotus Notes servers can be set to replicate information they contain within any other Lotus Notes server on the network, so that a change to a document on the server will automatically be shared with all other servers that contain the same document.

 

Setting up (adding) an E-mail or News account.

 

To set up an e-mail account, use an e-mail program such as Outlook ExpressOutlook Express is a Web browsing software that can help you exchange e-mail messages with colleagues and friends on the Internet or join newsgroups to trade/share ideas and information.

 

You will need the following information from your Internet Service Provider (ISP) or Local Area Network (LAN) administrator:

 

  • For e-mail accounts, you’ll need to know;
    • The type of Mail server you use (POP3, IMAP, or HTTP)
    • Your Account name and Password.
    • Name of the incoming mail server and,
    • If you are using POP3 or IMAP, the name of an outgoing mail server.

 

  • For a news account, you’ll need to know;
    • The name of the news server you want to connect to and, if required, your account name and password.

 

To add a mail or news account.

 

  1. On the Start menu, point to Programs, then click Outlook Express.
  2. On the Tools menu, click Accounts.
  3. In the Internet Accounts dialog box, click the Add
  4. Select either Mail or News to open the Internet Connection Wizard, and then follow the instructions to establish a connection with a mail or news server.

Tips.

  • After you set up your account, just double-click the Outlook Express icon on the desktop to begin sending and receiving e-mail.
  • You can get a free mail account from Hotmail, which uses HTTP servers.

 

E-mail addresses.

 

Each user has his own e-mail address (or mailbox) in form of computer storage space to receive messages.  The mailbox is accessed via a computer terminal within the system.  In addition, each user has a password to protect access to his/her own mailbox.

 

Messages are drawn to the user’s attention when they enter the system.

 

Components of an E-mail address.

 

An e-mail address consists of two parts separated by the @ symbol.  For example, if your e-mail address is [email protected]:

 

  • The 1st part of the address to the left side of the @ symbol refers to the person’s identity or login name. It is the name or identifier of the specific individual or organization, e.g., “drg”.

 

  • The 2nd part following the “@” symbol is the computer address. It is usually made up of 2 to 3 sub-parts to further identify the individual, organization, ISP or a country.  In this case:
    • “tropicalheat” identifies the business.
    • “.com” is the extension, which identifies the type of the organization.

 

The table below shows some extensions and what they represent: –

 

Extension Represents
.org A non-profit making organization
.edu An educational institution or organization
.com A commercial organization
.net Network
.mil Military
.gov government

 

Sometimes, the name of the country is included in the e-mail address.  E.g., [email protected] or [email protected].

 

In this case, “.co.uk” refers to a company in the United Kingdom, while “.co.ke” refers to a company in Kenya.

 

Examples of E-mail addresses;

 

[email protected]

[email protected]

[email protected]

[email protected]

[email protected]

[email protected]                   (free e-mail address)

[email protected]          (free e-mail address)

 

 

 

 

Exercise.

  1. (a). What is E-mail?

(b). Give TWO examples of e-mail software.

(c). Give an example of an e-mail address.

  1. Identify institutions whose e-mail addresses end with the following extensions:
    • .org ______________________________________________________
    • .gov ______________________________________________________
    • .edu ______________________________________________________
    • .com______________________________________________________
    • .net ______________________________________________________
    • .mil ______________________________________________________
  2. Identify the parts of the following e-mail address:

 

[email protected]

 

 

 

 

 

 

A         B           C    D

 

A _________________________________________________________________

B _________________________________________________________________

C _________________________________________________________________

D _________________________________________________________________

 

Reading E-mail Messages.

 

Purpose.

 

  • Once an e-mail message that has been sent to you arrives at your computer, to read the contents you must open it using the program you have installed for sending e-mail, e.g., Microsoft Outlook or Outlook Express.

 

  1. Open the e-mail program, e.g., Outlook Express from the Start menu or a shortcut on the desktop.

 

The Choose Profile dialog box appears to allow you to select your profile.

 

Note.  A User Profile is a group of settings that define how the e-mail program is set up for a particular user.  It also defines through the information services how a user can send, store, and receive messages.

 

  1. Select your profile by clicking the down arrow on the Profile Name box, and then click OK.

 

Usually, all incoming messages are stored in the Inbox when you connect to Outlook Express.  The Inbox displays all the e-mail messages that you have received.

 

  1. To open and read e-mail messages, click the Inbox icon either on the Outlook bar or on the Folders list, and then choose the message that you want to read.
  • To view the message in the preview pane, click the message in the message list.
  • To open the message in a separate window, double-click the message in the message list.

 

The lower grid of your screen will have the full message.

 

  1. When you have finished reading a message, you can close the window. Choose Exit on the File  This will take you back to the Outlook Express window.  If there are any e-mails in the Outlook that have not been sent, a message will appear prompting you to send the e-mail(s) at that particular time or you can send it later.

 

Tips

  • After Outlook Express downloads your messages, you can click the Send/Recv button on the toolbar, to read messages either in a separate window or in the preview pane.

 

  • To view all the information about a message, such as when it was sent, click the File menu, and then click Properties.

 

  • As you read the items in your items in your Inbox, you can reply to, forward, or file them in other folders that you create.

 

  • To save the message in your file system, click Save as and then select a format (mail, text or HTML) and location.

 

 

Reply to E-mail Messages.

 

Purpose.

 

  • If you have read a message, you may want to send a reply to the original sender.
  • If the original message that you are replying to was also copied to a no. of other people, you may want to send a reply to all of them.

 

When replying to a mail message, you can choose to reply with or without the original message insertion.  The original message, sometimes referred to as the History, appears in the body of the message, and is used for reference purposes.

 

Reply with the original message insertion.

 

  1. Open the message you want to reply.
  2. Click the Reply button in the Mail The Reply message window appears containing the message you are replying to at the bottom.
  3. Type the reply where the insertion point is.
  4. When you have finished typing and editing the reply, click the Send button (if you are online) to send the message.

 

Note.  If you click the Send button while you are offline, the mail will be placed in the Outbox folder and will automatically be sent the moment you are online.

 

Reply without the original message insertion.

 

To remove the original message, select the text, and then press the DELETE key or set options in the Options dialog box.

 

  1. On the Tools menu, click Options.
  2. Click the Reading
  3. Under When replying to a message box, click the down arrow, then select Do not include original message, then click
  4. Follow the procedure used to reply a message with the original message insertion.

This time, the Reply message window will not contain the message you are replying to at the bottom.

 

Note.  After replying to an e-mail, the E-Mail icon will indicate a checkmark showing that the mail has been replied to.

 

 

 

 

 

 

 

 

Creating and sending an e-mail message.

 

Purpose.

 

  • To communicate with another user who has an e-mail address. This is cheaper than sending fax or using the telephone especially for long distance calls.
  • It is also faster to send e-mail than to post a letter.

E.g., to send a letter around the world using e-mail takes some few minutes as compared to the weeks ordinary mails take.

 

  1. Start the Microsoft Outlook
  2. On the toolbar, click the New Mail Message

The message composition window is displayed.

 

  1. In the To… and/or Cc… boxes, type the e-mail addresses of each recipient.
    • If you want to sent copies of the message to other people, type in their e-mail addresses in the Cc… box, separating the addresses with a semicolon (😉.
    • To add e-mail names from the Address Book, click the book icon in the New Message window next to To, Cc, and then select names.

 

  • You can also send a Blind Carbon Copy (Bcc). In this case, the recipients entered receive the message but their names are hidden from other recipients of the message.  To use the Bcc box, click the View menu, and then select Bcc field.
  1. In the Subject box, type a message title.
  2. In the lower grid of the message composition window, type in the message that you want to send.

You can format the e-mail message using the formatting tools like, Bold, Font size, Underline, etc.

  1. When you have finished typing the message, editing, and spell checking, click the Send button on the New Message

 

Notes.

  • To save a draft of your message to work on later, click the File menu, then click Save. You can also click Save as to save a mail message in your file system in mail (.eml), text (.txt), or HTML (.htm) format.

 

  • A message that returns to the sender because it cannot reach its destination is referred to as a Bounced message.

 

Checking the spelling in mail messages.

 

Before sending a mail message, you can spell check it to correct any spelling mistakes in the mail.

 

Outlook Express uses the spelling checker provided with Microsoft Office 97 programs, such as Microsoft Word, Microsoft Excel, and Microsoft PowerPoint.

 

  1. In the New Message window, click the Spelling button on the toolbar, (or click the Tools menu, and then choose Spelling).
  2. The Spelling dialog box appears. The misspelt words are highlighted and shown in the dialog box.  Choose the correct word by selecting it, and then click the Change

If the word or phrase is correct but is not in the dictionary, click Ignore.

  1. Once spell checking of the mail is complete, and a dialog box appears, click OK.

 

 

Formatting e-mail message text.

 

To add special emphasis or structure to message text-such as bold, color, or bulleted lists, and also to add graphics and links to Web sites in your mail messages, use Hypertext Markup Language (HTML) – the standard language for formatting text for the Internet.

 

 

 

 

To use HTML formatting on all outgoing messages.

 

  • When you create messages using HTML formatting, only mail programs that support HTML can read the formatting. If the recipient’s mail or newsreading program does not read HTML, the message is displayed as plain text with an HTML file attached. The recipient can view the attached file by opening it in any Web browser.

 

To send the message in HTML formatting;

 

  1. In the main window, click the Tools menu, click Options, then click the Send
  2. In the Mail Sending Format or News Sending Format sections, click HTML.

 

To use HTML formatting on an individual message.

 

In an e-mail message window, make sure HTML formatting is turned on, i.e., Click the Format menu, then choose Rich Text (HTML). A black dot appears by the command when it is selected.

 

To change the font, style, and size of text.

 

You can change the way the text looks for all your messages or you can make changes to selected text within a message.

 

To change the text style for all messages.

 

  1. On the Tools menu, click
  2. Click the Compose tab, then click the Font Settings

 

To format text within individual messages.

 

  1. Select the text you want to format. To change the font for an entire message, click the Edit menu, then click Select All.
  2. On the Formatting toolbar, click the buttons for the options you want.

 

To format a paragraph.

 

  1. Click anywhere in the paragraph, or select the text you want to format.
  2. Use either the Formatting toolbar or the commands on the Format menu to change the text.

 

To                                                                               Do this

 

Change the indentation of a paragraph                      Click the Increase Indent or Decrease Indent button on the Formatting toolbar.

 

Add a horizontal line                                                  Click where you want the line to appear, and then click the Insert Horizontal line button on the Formatting toolbar.

 

Format text written in Rich Text (HTML) mode      Click the Format menu, point to Style, and then choose an option.

 

To create a numbered or bulleted list.

 

  1. In your message, click where you want the list to start.
  2. On the Format menu, point to Style, then click either Numbered List or Bulleted List.
  3. Type the first item in the list. When you press ENTER, another list entry is started on the next line.

To end the list, press ENTER twice.

 

Inserting items in a message.

 

To insert a Business card in all messages.

 

  1. On the Tools menu, click Options, then select the Compose
  2. In the Business Cards section, select the Mail or News check box, and then select a business card from the drop-down list.

 

Notes.

 

  • To change information in a business card, click the Edit

 

  • To add a business card or signature to an individual message, in a message window, click the Insert menu, then click either Signature or My Business Card.

 

To include a sound in a message.

 

  1. Click anywhere in the message window.
  2. On the Format menu, point to Background, and then click Sound.
  3. Enter the name of the file you want to include and the number of times you want the file to play.

 

To insert a picture in a message.

 

  1. In the message, click where you want the image to appear.
  2. On the Insert menu, click Picture, then click Browse to find the image file.
  3. Enter Layout and Spacing information for the image file as needed.

Notes.

 

  • If message recipients are not able to view your inserted images, click the Tools menu, and then click Options. Click the Send tab, click HTML Settings, and then make sure that Send pictures with messages is selected. Then resend your message.

 

  • To insert a background picture in your message, in the message window, click the Format menu, point to Background, then click Picture. Click the Browse button to search for the file you want to use.

 

Attaching files to e-mail messages.

 

Purpose.

 

  • You can attach a copy of any type of file such as a document, spreadsheet, graphic image or a presentation to your e-mail messages.

 

  1. Click the New Message
  2. In the Message Composition dialog box, enter the e-mail address and type in the message to be sent.
  3. Click where you want the file attachment to appear, then click the Insert File button to display the Insert File dialog box.
  4. Locate the folder that contains the file you want to attach, and then click the file.

To select multiple files, hold down the CTRL as you click each of the files.

  1. Click the OK

The attached file is displayed as an icon in the body of the message.  The icon indicates the file type and name.  e.g., Sales Results.xls

  1. Click the Send

 

To open or view the attached file.

 

Documents that contain file attachments display a paper clip image in the view or folder next to the document file.

Once the document is open, Microsoft Outlook displays an icon representing the attachment.

 

Note. You must have the application in which the attachment was composed in order to open it.  The MIME (Multi-purpose Internet Mail Extension) type of file enables Internet browsers to access an Internet mail file without prompting the user to specify the program used to create the attached file.

 

  1. In the Inbox, select the e-mail message that contains the attachment.
  2. Double-click the e-mail message to open it.
  3. Double-click the icon that represents the attachment.

 

 

Deleting an attachment.

 

  1. Open the e-mail message that contains the attachment.
  2. To delete the attached file, click the file icon, then press the Delete

 

Organizing E-mail messages.

 

Purpose.

 

  • You can use Outlook Express to organize your incoming messages and make it easy to send mails.

 

To use your online time efficiently, use Outlook Express to find messages, automatically sort incoming messages into different folders, keep messages on a mail server, or delete them entirely.

 

Organizing the Inbox.

 

You can organize the messages in your Inbox quickly by sorting them.

 

To quickly sort messages by Subject, Sender or the Date received, click on the respective column header.  E.g., to sort your messages in alphabetical order by sender, click on From in the column header.

 

To create a Mail folder.

 

  1. On the File menu, click New, then choose Folder.
  2. Enter the name of the folder in the Name box, e.g., My Own.
  3. Select the Inbox folder so that the mail folder created will become a subfolder of the Inbox.
  4. You can add details, such as a description of the folder in the Description box, then click OK.

 

To move or copy a message to another folder.

 

  1. In the message list, select the message (s) you want to move or copy.
  2. On the Edit menu, click Move to Folder or Copy to Folder, then select the folder you want to move or copy the message to.

 

To delete a mail message.

 

  1. In the message list, select the message.
  2. On the toolbar, click the Delete button (or press the Delete key).

 

Notes.

 

  • To restore a deleted message, open the Deleted Items folder, and then drag the message back to the Inbox or other folder.

 

  • If you don’t want messages to be saved in the Deleted Items folder when you quit Outlook Express,
    1. Click the Tools menu, then click Options.
    2. On the Maintenance tab, select the checkbox labeled Empty messages from the ‘Deleted Items’ folder on exit.

 

  • To manually empty all deleted items,

 

  1. Select the Deleted Items
  2. On the Edit menu, click Empty Deleted Items Folder.

 

Sending a Web page by e-mail.

 

Purpose.

 

  • You may find some interesting and useful material on the Internet that you would like to share with friends and colleagues.

 

You can send Web pages by e-mail to other people even if the recipients are not connected to the Internet.

 

  1. Access the Web page you want to send.
  2. Click the File menu, point to Send, then click Page By E-mail or Link By E-mail.
  3. If necessary, choose the correct profile to use from the Profile dialog box, i.e., Outlook Express, and click OK.
  4. In the Message dialog box, enter the address of the recipient, then click the Send

 

Note. You must have an e-mail account and an e-mail program set up on your computer.

 

Blocking Unwanted messages.

 

You can control the mail and news messages you get in Outlook Express . You can block certain people from sending you mail, you can hide conversations that don’t interest you, and you can guard against being sent damaging code in mail by setting security levels.

 

To block messages from a sender or domain.

 

You can block messages from a particular sender or domain.

 

  • The Domain is the name following the @ symbol in an e-mail address.

 

  • Domain – A group of networked computers that share information & resources.

 

When you block a sender or domain, no e-mail or news message from that sender or domain will arrive in your Inbox or in the news messages you read.

E-mail from blocked senders goes directly into your Delete folder while Newsgroup messages from blocked senders are not displayed.

  1. From your e-mail Inbox or the list of messages in a newsgroup, select a message from a sender you want to block.
  2. On the Message menu, click Block Sender.

The e-mail address of the sender will appear in the Address box. You can type a different address or domain in the Address box if you wish.

  1. Select the blocking option you want: mail, news, or both kinds of messages.

 

Important.  Blocking a sender applies to standard POP mail only. It does not apply to HTTP mail (Hotmail) or IMAP messages

 

Differences between E-mail and General Post office mail.

 

  • E-mail is computerized, while Post office mail is manually operated.
  • Post office mail is slow, while E-mail is fast & has a wide area of coverage.
  • E-mail is more secure.

 

Advantages of E-mail.

 

Electronic mail has several advantages over regular mail.

 

  • It is cheap & economical.

It costs almost nothing to transmit an e-mail message over the network, i.e., there is no need for stamps, envelopes, etc.

  • It is secure, i.e., access to a user’s mailbox can be restricted by use of a password.
  • It is faster, i.e., mails can be sent instantly.

The delivery of an e-mail message normally takes seconds or minutes, depending on the distance to the receiver.

  • It is efficient, i.e., a message prepared only once can be sent to several people.
  • It is convenient.

With E-mail, you can send your messages when it is convenient for you and your recipients respond at their convenient times.

 

  • E-mail is cheaper in terms of the time invested in preparing the message.

 

The expectations and culture of sending & receiving e-mail are different from that of sending regular letters.  Regular business letters & inter-office memos are expected to be error-free and formatted according to certain standards.  In contrast, most e-mail users accept less well-formatted messages and slight typographical errors are overlooked. So, less time is spent perfecting the appearance of the message.

 

  • E-mail can act as a substitute for the Telephone calls, thus allowing the user to avoid telephone tag (i.e., the process of repeatedly exchanging voice mail messages because you or the other person may not be available when the other calls).

E-mail can often communicate enough of a message so that the entire “conversation” will take less time than a phone call.

 

E-mail is particularly effective for multinational organizations, which have people working in different time zones around the world.

 

Disadvantages of E-mail.

 

  • The initial installation cost is higher.
  • Messages may be lost before they are read due to virus infections.
  • Messages may not be kept for future reference due to the high cost of storage, i.e., it requires regular deletion of messages from the hard disk.

 

Exercise.

 

  1. How does one send an e-mail message?
  2. What is the advantage of filing e-mail messages when you can leave them in the Inbox and still have them for future reference?
  3. List THREE levels of importance one can set on an e-mail message.
  4. Lucille has received an e-mail message that contains an attachment. Can she use any application to open the attached file? Explain.
  5. What are the advantages of e-mail over the ordinary post office mail.
  6. Give THREE differences between electronic mail and the Post office mail?

 

 

Using the Address Book.

 

Purpose.

 

  • The Address Book is a directory of personal details, including e-mail addresses, for the people to whom you send messages (called Contacts).

 

It is used to store/keep track of e-mail addresses, mailing addresses, phone numbers, and other information about your friends and also provides space for notes.

 

You can store such addresses in the Address Book so as to address mails more easily, i.e., each time you want to send e-mail messages, you simply select the names from the list of addresses.

This will save the time used to enter lists of e-mail addresses as well as help maintain their accuracy.  E.g., an e-mail address like [email protected] can be difficult to remember.  In addition, one can easily make a typing error when typing the address.

 

The Address Book is accessible from Internet Explorer, Outlook Express and NetMeeting, thus enabling you to keep one list of addresses that are accessible by various programs.

 

To add a contact to the Address Book.

 

  1. To open the Address Book, click the Address Book

There can be several types of address books in the Address Book dialog box including the Global Address list and Personal Address Book.

  1. In the Show names from the box, select the type of address book you want to use.

 

The Global Address list is the address book that contains all e-mail addresses for users, groups, and distribution lists in your organization that you can address messages to.  The Administrator creates and maintains this address book.

 

The Personal Address Book is the address book used to store personal distribution lists you frequently address messages to, such as a list of your friends.

 

  1. Click the New Entry
  2. Specify the entry type of the contact, i.e., whether it is an Internet address or an entry for a distribution list.
  3. Type in the display name for the address as well as the full e-mail address.
  4. Complete the dialog box with the rest of the contact details using the other tabs, e.g., Business or Phone Numbers, then click OK.

The contact address is added to the Address Book.

 

To edit a contact in the Address Book.

 

  1. Open the Address Book.
  2. Select the contact that you want to edit.
  3. On the File menu, click Properties.
  4. Make the necessary changes to the information, then click OK.

 

To create a contact from a mail message.

 

When you receive a mail message, you can add the sender’s details (name and e-mail address) to your Address Book.

 

  1. From the Inbox, right-click a message.
  2. Select Add sender to Address Book, from the shortcut menu that appears.

 

To delete a contact from the Address Book.

 

  1. Open the Address Book.
  2. Select the address that you want to remove from the Address book.
  3. Click the Delete button (or press the Delete key).
  4. Click Yes to confirm that you want to delete the name or entry.

 

To create a distribution list.

 

If you send mails to the same group of people frequently, you can create a group address list.  Group address lists are known as Distribution lists.

 

When you address a message to that group, each individual in the group receives it.

 

Note.  You must have a Personal Address Book set up in order to be able to create a personal distribution list.

 

  1. Open the Address Book.
  2. Click the New Entry
  3. In the Select the entry type box, click Personal Distribution List, and then click OK.
  4. In the Name box, type a name for the group, e.g. Sales Dept., then click the Add/Remove Members
  5. To add members to the group, select a contact or name from the left hand list box, then click the Members button (or double-click on a name) to move the name to the right list box.

The contact is copied to the Personal Distribution List box.

  1. Repeat step 5 until you have all the names you want in your group in the Personal Distribution List, then click OK.

The group or distribution list is usually listed in the Address Book.

 

To send a message using the Address Book or distribution list.

 

  1. In the Microsoft Outlook window, click File then select the New Mail Message.
  2. Click the To… button to open the Address Book.
  3. Select the contact names from the list or select the distribution list, then click on To ->.

 

Note. To see the full e-mail addresses, select the name of the person from the lists and click on Properties button.

 

  1. Click OK to return to the message composition dialog box.
  2. Type out the rest of the message and click on Send.

 

Exercise.

 

  1. What are the advantages of using the Address Book as opposed to typing e-mail addresses each time you send e-mail?

 

READING MAIL MESSAGES OFFLINE.

 

Once you have opened the E-mail program, it is not necessary for you to be connected directly so that you can read & write your e-mail messages.  You may choose to work offline to save on costs.

 

When you are offline, Outlook Express downloads mail messages to your local computer. When you connect (or choose to work online) again, messages in your Outbox are sent, messages you marked for deletion are removed, and all other actions taken offline are completed at once.

 

There are 2 situations where it is beneficial to use Outlook Express offline:

 

  • If your ISP charges you by the hour or if you have only one phone line. Under these conditions, you might want to reduce time spent online.

 

  • If you use a Laptop to read your messages while you are traveling or any other time you are not connected to the Internet.

 

To set up Outlook Express to reduce online time.

 

  1. On the Tools menu, click Options.
  2. On the Connection tab, select Hang up after sending and receiving.

If you connect to an IMAP or HTTP server, click the server name in the folder list, and then make sure that the items you want to view offline are checked.

 

This procedure can be used to set up Outlook Express so that it automatically disconnects after you select Send and Receive from the Tools menu.

You can then read and compose messages offline without incurring charges or tying up a phone line.

 

Note.  To reconnect to send or receive messages, click the Tools menu, point to Send and Receive, and then select the option you want.

 

To read messages while you are away from your Internet connection.

 

  1. On the Tools menu, select Options, then click the General
  2. Under the field labeled If my computer is not connected at this time, select Connect only when not working offline.

If you connect to an IMAP or http server, click the server name in the folder list, make sure

that the items you want to view offline are checked, and then click Sync Account.

 

  1. On the File menu, click Work Offline.

 

Note.  To check the type of account you have, click the Tools menu, and then click Accounts. Select your e-mail account and then click Properties. The account type is listed on the Advanced tab.

 

Viewing and posting to Newsgroups.

 

What are newsgroups?

 

A Newsgroup is a collection of messages posted by individuals to a News server (a computer that can host thousands of newsgroups).

 

Some newsgroups are “owned” by someone who reviews the postings, can answer questions, delete inappropriate messages, etc.

Anyone can post messages to a newsgroup. This is because, Newsgroups do not require any kind of membership or joining fees.

 

To use newsgroups in Outlook Express, your Internet Service Provider must offer links to a news server. After you set up an account for the server you want in Outlook Express, you can read and post messages in any of the newsgroups stored on that news server.

 

 

To switch between mail and news reading.

 

  • In the Folders list, click Inbox to go to your e-mail, or click a news server name or specific newsgroup to visit newsgroups.

 

To find newsgroups of interest.

 

  1. In the Folders list, click a server name, then click the Newsgroups
  2. In the Display newsgroups which contain box, type the words you want to search for.

 

 

To subscribe to a newsgroup.

 

Subscribing ensures that the newsgroup is included in your Folders list for easy access.

 

You can subscribe to a newsgroup in any of the following ways:

 

 

  • When adding a news server, Outlook Express prompts you to subscribe to newsgroups on that server.

 

  • Click a news server name in your Folders list, and then click the Newsgroups Select the newsgroup that you want to subscribe to, and then click the Subscribe button.

 

Note: When you double-click a name in the Newsgroup list, a subscription is automatically generated.

 

 

  • When you click a newsgroup, its name appears in your Folders list. Right-click the name, and then click Subscribe.

Tips.  To cancel your subscription to a newsgroup,

  1. Click the Newsgroups button, click the Subscribed tab, select the group you want, and then click the Unsubscribe

Or

Right-click the newsgroup in your Folders list, then click Unsubscribe.

 

To view a newsgroup without subscribing to it.

 

To find out if a specific newsgroup is right for you, read some of the messages in it.

 

  1. From the Tools menu, select Newsgroups to open the Newsgroup Subscriptions dialog box.
  2. Select the news server you want in the Accounts All of the newsgroups on that server appear on the All tab.
  3. Select the newsgroup you want to view, and then click Go To.

 

Note.  The first time you view a newsgroup, it may take several minutes to download the messages. The next time you go to that newsgroup, it downloads faster, because Outlook Express downloads only new messages.

 

To read newsgroup messages.

 

Go to a newsgroup and look through the message list for a message you want to read (you may need to scroll).

 

  • To view the message in the preview pane, click the message once.

 

  • To view the message in a separate window, double-click the message in the message list.

 

To read and send international messages.

 

Outlook Express can usually display messages in the language in which they were sent. However, some messages, particularly those from newsgroups, often do not have enough information (or the information is incorrect) in the header file to display the correct language.

 

To change the language encoding for a message you are reading.

 

  • In the message window, click the View menu, point to Encoding, and then click the language encoding you want to use.

 

To set the default encoding for reading messages.

 

  1. On the Tools menu, click On the Read tab, click Fonts.
  2. Select a language at the top, and then click the Set as Default

 

Posting messages to newsgroups.

 

There are several ways that you can post messages, depending on whether you are posting a new message or replying to one and how widely you want it distributed.

 

  1. In the Folders list, select the newsgroup you want to post a message to.
  2. On the toolbar, click the New Post

 

Note. To send your message to multiple newsgroups on the same news server, click the icon next to Newsgroups in the New Message dialog box. In the Pick Newsgroups dialog box, hold down the CTRL key to select multiple newsgroups, and then click Add.

  1. Type the Subject of your message. Outlook Express cannot post a message that does not contain a subject.
  2. Compose your message, and then click the Send

 

To reply to a newsgroup message.

 

  1. In the message list, click the message you want to reply to.
  2. To reply to the author of the message by e-mail, click the Reply button on the toolbar.

To reply to the whole newsgroup, click the Reply Group button on the toolbar.

 

  1. Type your message, and then click Send.

 

Note.  To view information about a newsgroup message, such as when it was sent, select the message, click the File menu, and then click Properties.

 

To prevent newsgroup messages from automatically downloading.

 

On the Tools menu, click Options.

On the Read tab, clear the following check box: Automatically download messages when viewing in the Preview Pane.

 

To view newsgroups efficiently.

 

View only unread news messages in a newsgroup.

 

  1. Open the newsgroup, click the View menu, point to Current View, and then click Hide Read Messages.

 

View the replies to a particular message in a newsgroup.

 

  1. Click the plus sign ( + ) next to the message. The replies to that message appear below it. A message with its replies is called a “conversation.”

 

To watch a conversation.

 

In both mail and news, you can watch a conversation that is of particular interest you. A conversation is an original message and all its replies.

  1. In your Inbox or newsgroup message list, select the conversation you wish to watch.
  2. On the Message menu, click Watch Conversation.

If your message list’s Watch/Ignore column is turned on, the watch icon will appear next to all the messages of a watched conversation.

 

READING NEWSGROUP MESSAGES OFFLINE.

 

Offline newsreading enables you to read newsgroup messages without being connected to the Internet, saving connection costs.

 

To do this,  you must subscribe to the newsgroup whose messages you want to read offline, mark it to specify whether you want to see headers or whole messages, and then transfer them to your computer (synchronize). Once this is done, you can log off from the Internet and then read the messages at your leisure.

 

Reading message headers only, gives you the subject, author, and size of the message.

 

To set up newsgroups for offline news reading.

 

For newsgroups you subscribe to, you can set up Outlook Express to make messages or headers available offline by synchronizing. This enables you to read them at your leisure when you are not connected to the Internet.

 

  1. From the Folders list, select a news server.
  2. In the main window, select one or more newsgroups you subscribe to whose messages you want to read offline. (To select multiple newsgroups, hold down the CTRL key while you click the newsgroups.)
  3. Click the Settings button, and then click to mark what you want transferred from the server to your computer during synchronization:
    • All Messages,
    • New Messages Only (new to the server since you last synchronized), or
    • Headers Only (subject, author, date, and size of message).
  4. Click the Sync Account

 

Exercise.

 

  1. (a). When can you work offline?

(b). Why should you work offline?

 

Methods of Accessing Computer and Locating Files.

 

  • Gopher:

 

This is a client/server tool that enables the user to locate almost all textual information stored on Internet servers through a series of easy-to-use or understand, hierarchical menus that provide point-and-click interfaces.

 

The Internet has thousands of Gopher server sites throughout the world.  Each gopher site contains its own system of menus listing related topics, local files, and other relevant gopher sites.

To search for a specific topic or select a related item from a menu, activate the gopher software.  The server will automatically transfer you to the appropriate file on that server or the selected server wherever it is located in the world.  Once on the distant server, you are presented with more menus of files and Internet addresses of other gopher site servers that might interest you.  You can then move from site to site locating information that you want anywhere in the world.  After finding the information or files you want, you are free to browse, read them online, or download them onto your own computer for searching for text that appears in gopher menus.

 

  • Archie:

 

This is a tool for locating data on the Internet that performs keyword searches of an actual database of documents, software, and data files available for downloading from servers around the world.

 

An individual Archie database can list only a small percentage of the files in the world.  However, clicking on the relevant listing from one Archie server will bring you to another computer system where relevant files are stored.  While on the other computer, the Archie server may provide other relevant references, allowing you to continue your search for related files, moving from database to database, library to library, until you locate what you need.

 

Archie database searching uses the subject keywords entered such as “telecommuting” or “inflation” to display a list of sites that contain files on that topic.  Once you find the files you want, you may use a file transfer program to download them.

 

  • WAIS (Wide Area Information Servers):

 

This is a tool for locating data on the Internet that require the name of the databases to be searched based on keywords.

Once you specify specific database names and key identifying words, WAIS searches for the keywords in all the files in those databases.  When the search is completed, you are given a menu listing all the files that contain your keywords.

 

  • The Word Video Web:

 

The Web is another information retrieval tool similar to gophers, Archie, and WAIS.  It is widely used for commercial purposes on the Net due to the fact that, it is attractive, easy to use, and helpful in publishing or providing information to anyone interested.

 

  • Home Page:

 

Anyone willing to offer information through the Web must first establish a Home Page (a WWW text & graphical display that welcomes the user and explains the organization that has established the page).  The Home page will lead the user to other pages.

All the pages of an organization are known as a Website.

 

Home pages combine text, hypermedia, graphics and sound, unlike the other methods of locating information on the Net, which are text-based.  This means that, home pages can handle all types of communication, while making it easy to link resources that are far apart.

 

Graphics allow organizations to communicate more effectively, making their own material more appealing to the eye, more informative, and easy to understand.

 

Hypermedia provides a point-and-click connection to related information within the same document, between documents on the same computer, or to documents located on another computer anywhere in the world (as long as the computer is connected to the Net, and the hypermedia connection has been programmed in).

 

Sound allows some of the Web displays to talk or play music.

 

Note.  The specific hypermedia technology used in the Web is known as Hyperlinks.

Within any web document, there are certain words or graphics that are highlighted (usually appear bold, in a different colour, underlined, or a combination of these).  The highlighted objects have hyperlinks embedded within them that contain the path to another location within the same document, a document on the same computer, or a document on another computer.

Hyperlinks allow the user to move with ease within complex documents or across the network.  If the reader of the document wants more information on the highlighted word, he/she double-clicks the word, and quickly that other information will be displayed, even if it is stored in another part of the world.

 

Advantages of Hyperlinks.

 

  • It is easy to use.
  • The user is free to jump from place to place following his/her own logic and interest, and does not have to move according to a static, pre-programmed, linear sequence.

The user moves around almost as easily as a book reader might follow keywords and jump around an encyclopedia.

 

To navigate the Web requires a graphics Computer to link to the Internet.  The user must also have a special software tool to navigate the Web known as Web Browser.

 

 

BENEFITS FROM THE USE OF THE INTERNET.

 

  • Reduces the Cost of Communication.

 

Before the Internet, organizations had to build their own Wide Area Networks or subscribe to Value-Added Network (VAN) service.

Many organizations find the Internet more cost-effective than building their own networks or paying VAN subscription fees.  Organizations use the Internet to fulfill a wide range of communication needs.  This lowers other communication costs, including their network management expenses, telephone and Fax costs.

Reduced communication costs are beneficial particularly to small businesses because it sometimes enables them to compete with larger companies in the markets that would otherwise be closed to them.

 

  • Enhances Communication & Co-ordination.

 

Global companies use the Internet as an important instrument for coordinating their activities.  Such companies have set up internal Web sites to keep employees informed about company developments.  Through the Web, employees are able to see a company Calendar, the employee Policy manual, product Brochures, interactive Training tools, and even stock quotes.

 

The Internet has made it easier and less expensive for companies to co-ordinate small staffs when opening new markets or working in isolated places, because they do not have to build their own networks.

 

  • Accelerates the Distribution of Knowledge.

 

To speed product development and also to react to an emerging problem, information gathering must be quick and easy.

 

The Internet is very useful in the modern society, which is increasingly dependent on knowledge.  Organizations are using E-mail and the availability of databases all over the world to gain access to information in such areas as Business, Science, Law, and Government.  The Internet can quickly link a computer user sitting at a computer screen to mountains of data (including Graphics) all over the world, which would otherwise be too expensive and too difficult to get.

 

  • Improves Customer service and satisfaction.

 

Organizations can also use the Internet to communicate efficiently to make product information, ordering and technical support easier and immediately available.

A company can establish a Website on the Internet in order to distribute useful product information to its customers and product users.  It can also use the Internet to give engineering support to its customers without the involvement of engineering staff.

 

  • Facilitates Sales and Marketing.

 

The Internet provides opportunities for firms to market and sell their products in a way that does not offend others.  This is because, the Internet is a passive instrument, i.e., it requires potential customers to seek out offerings by companies rather than having those companies actively reach out to potential customers, as is the case in most marketing and advertising.

 

Retailers update their Web page offerings frequently as required.  Suppliers can also update technical materials used by customers easily.  Therefore, the Internet assist buyers and sellers make contacts.

Firms use their Websites to distribute more marketing information.  A firm can include its Web address in product advertisements and design their site for visitors to browse information on pricing, press releases on new products, technical manuals and sales brochures.

 

PROBLEMS FACING THE INTERNET.

 

  • Lack of Security.

 

Lack of security is one of the reasons why the Internet, while being widely used to facilitate transactions, is still in limited use to carry out transactions.

When large amounts of data are stored in electronic form, they are exposed to more kinds of threats/dangers than when they exist in manual form.

 

Through data communication networks, information systems in different locations on the Internet are interconnected.  The potential for unauthorized access, abuse or fraud is not limited to a single location but can occur at any access point in the Internet.

 

Internet Hackers have found ways of stealing passwords as they pass through one site and use them to break into computer system at other sites all over the world.

 

The hackers can get access to company’s strategic business plans, profit reports, product development information, pricing data, marketing plans, sales contracts, and scientific research data.  Such information is too sensitive and companies are unwilling to have it accessed by unauthorized people.

 

  • Technology Problems.

 

  • The Internet lacks standards for accessing the net and sending e-mails. A no. of incompatible ways for accessing the net exist, allowing specific users to perform certain functions but not others.

 

  • The lack of standards also affects the ability of organizations to establish a stable link to the Internet. As the traffic on the Internet becomes more complex, it can bring problems if it does not have good technical support.

 

  • Many people and organizations are sending so much data through the Net, much of it in graphics form, such that telecommunication links are already overloaded. Frequent users are unable to access the net, while those who use the graphics-based Web regularly find connecting to the intended Server very slow or even almost impossible during busy times.

 

  • Moreover, the growing need for bandwidth due to graphics will only expand as the transmission of sound and full-motion video expands. All this is raising the cost of using the Net.  Some firms are already discovering that they need more expensive telecommunications connections, Workstations or higher speed computers with improved graphics capability, and even Information system specialists with skills related specifically to the Internet.

 

  • Individuals and organizations in less developed countries with poor Telephone lines, limited hardware and software capacity or Government controls on communication will not be able to take full advantage of Internet resources.

 

  • Due to the fact that there is no a comprehensive method of locating and keeping track of pages in the World Wide Web (www), Internet users often spend a lot of time in futile (unsuccessful) searches, despite the many new tools and planned indexes to the Web. There is no good technology enough to filter/sort out irrelevant information while allowing people to access the specific information they need.

 

  • Legal Issues.

 

Until a greater clarity on several legal issues is obtained, doing business on the Internet will become unreliable.

 

Laws governing E-commerce are mostly non-existing or are just being written.

There are several open questions that still exist such as, the legality of E-mail contracts, the role of electronic signatures, and the application of copyright laws to electronically copied documents.

 

  • Anti-Commercial culture.

 

Initially, the Internet was a scientific and academic tool.  As it grew, a strong anti-commercial culture grew with it.

Internet users have shown themselves unwilling to accept the Internet mail.  Many commercial users also fear that allowing commercial organizations to add very many unasked for marketing messages will make the Internet E-mail difficult to manage.

Thus, while businesses remain free to use the Internet for E-mail, research, and other forms of information exchange, they will have to learn new ways to do their marketing on the Internet; ways that do not offend the other users.

 

Exercise I.

 

  1. State the various methods of accessing computer and locating files.
  2. Describe the main benefits from the use of the Internet.
  3. Give a brief view of the main problems of the Internet.

 

Exercise II.

 

  1. Briefly describe four advantages of using Internet to disseminate information compared to other conventional methods. (8 marks).
  2. One of the problems of using Internet for business is insecurity. What are some of the other problems and what controls should be put in place in order to solve the problems?. (4 marks).
  3. Your manager wishes to be connected to the Internet. He already has a powerful Personal Computer (PC), a Printer and access to a Telephone line.  However, he understands that he will need a Modem.

 

Required:

  • State why a Modem is required to connect him to the Internet. (2 marks).
  • Suggest any four application areas in which you would expect a Supermarket retail manager to use the Internet. (4 marks).

 

 

 

 

 

 

 

 

 

 

Moi Girls High School Eldoret KCSE 2025 Joint Exam Papers & Answers

Moi Girls High School Eldoret KCSE 2025 Joint Exam Papers & Answers

MOI GIRLS PHYC PP3 CONF.pdf
MOI GIRLS PHYC PP3 CONF.docx
MOI GIRLS PHYC PP3 2025 PREDICTIONS.pdf
MOI GIRLS CHEM PP3 CONF.pdf
MOI GIRLS CHEM PP3 2025 PREDICTIONS.pdf
MOI GIRLS CHEM PP3 2025 PREDICTIONS.docx
MOI GIRLS BIO PP3 CONF.pdf
MOI GIRLS BIO PP3 CONF.docx
MOI GIRLS BIO PP3 2025 PREDICTIONS.pdf
MOI GIRLS CRE PP1 2025 PREDICTIONS.pdf
MOI GIRLS CRE PP1 2025 PREDICTIONS.docx
MOI GIRLS HOME SCI PP3 2025 PREDICTIONS.pdf
MOI GIRLS HOME SCI PP3 2025 PREDICTIONS.docx
MOI GIRLS HOME SCI PP2 2025 PREDICTIONS.pdf
MOI GIRLS HOME SCI PP2 2025 PREDICTIONS.docx
MOI GIRLS HOME SCI PP1 2025 PREDICTIONS.pdf
MOI GIRLS HOME SCI PP1 2025 PREDICTIONS.docx
MOI GIRLS COMP PP2 2025 PREDICTIONS.pdf
MOI GIRLS COMP PP1 2025 PREDICTIONS.pdf
MOI GIRLS COMP PP1 2025 PREDICTIONS.docx
MOI GIRLS MATH PP2 2025 PREDICTIONS.pdf
MOI GIRLS MATH PP2 2025 PREDICTIONS.docx
MOI GIRLS MATH PP1 2025 PREDICTIONS.pdf
MOI GIRLS BIO PP2 2025 PREDICTIONS.pdf
MOI GIRLS BIO PP1 2025 PREDICTIONS.pdf
MOI GIRLS PHYC PP2 2025 PREDICTIONS.pdf
MOI GIRLS PHYC PP2 2025 PREDICTIONS.docx
MOI GIRLS PHYC PP1 2025 PREDICTIONS.pdf
MOI GIRLS CHEM PP2 2025 PREDICTIONS.pdf
MOI GIRLS CHEM PP2 2025 PREDICTIONS.docx
MOI GIRLS CHEM PP1 2025 PREDICTIONS.pdf
MOI GIRLS BST PP2 2025 PREDICTIONS.pdf
MOI GIRLS BST PP2 2025 PREDICTIONS.docx
MOI GIRLS BST PP1 2025 PREDICTIONS.pdf
MOI GIRLS AGRI PP2 2025 PREDICTIONS.pdf
MOI GIRLS AGRI PP2 2025 PREDICTIONS.docx
MOI GIRLS AGRI PP1 2025 PREDICTIONS.pdf
MOI GIRLS AGRI PP1 2025 PREDICTIONS.docx
MOI GIRLS KISW PP3 2025 PREDICTIONS.pdf
MOI GIRLS KISW PP3 2025 PREDICTIONS.docx
MOI GIRLS KISW PP2 2025 PREDICTIONS.pdf
MOI GIRLS KISW PP1 2025 PREDICTIONS.pdf
MOI GIRLS KISW PP1 2025 PREDICTIONS.docx
MOI GIRLS ENG PP3 2025 PREDICTIONS.pdf
MOI GIRLS ENG PP3 2025 PREDICTIONS.docx
MOI GIRLS ENG PP2 2025 PREDICTIONS.pdf
MOI GIRLS ENG PP1 2025 PREDICTIONS.pdf
MOI GIRLS ENG PP1 2025 PREDICTIONS.docx
MOI GIRLS GEO PP2 2025 PREDICTIONS.pdf
MOI GIRLS GEO PP1 2025 PREDICTIONS.pdf

FORM 4 AGRICULTURE SCHEMES OF WORK

SCHEME  OF  WORK           AGRICULTURE  FORM  FOUR             TERM  ONE  

WK/NO

L/

NO

TOPIC   /

SUBTOPIC

LESSON / SPECIFIC

OBJECTIVES
TEACHING / LEARNING

ACTIVITIES
MATERIALS

/

RESOURCES

REF. REM.

1

1

POULTRY PRODUCTION

Composition of an egg.

By the end of the lesson, the learner should be able to:

Identify parts of an egg.

Describe the parts of an egg.

Drawing and labeling an egg.

Breaking an egg to examine its internal structure.

Eggs,

 

Chart – parts of an egg.

KLB BK IV

Pg 1-2

 

Longhorn Bk IV

Pg 1-2

 

2

Incubation of  eggs.

Define the term incubation of eggs.

State characteristics of eggs for incubation.

Q/A and discussion.   KLB BK IV

Pg 3-4

Longhorn Bk IV

Pg 2

 

3

Egg candling.

Describe candling of eggs. Practical activity. Observing internal structure of an egg.

Make deductions from the observations.

 

Cardboard boxes,

Torch, eggs.

 

KLB BK IV

Pg 4

 

Longhorn Bk IV

Pg 3

 

4

Natural incubation.

 

 

State merits & demerits of natural incubation.

Identify management practices of an incubator.

 

Q/A & discussion.

Exposition, discussion & oral questions.

Nesting box. KLB BK IV

Pg 5-6

 

Longhorn Bk IV

Pg 3-4

 

2

1

Artificial incubation.

Outline conditions necessary for artificial incubation.

 

    KLB BK IV

Pg 7-8

Longhorn Bk IV

Pg 5-6

 

2

Management of an incubator.

 

Merits & demerits of artificial incubation.

 

Highlight management practices of an incubator.

 

State merits & demerits of artificial incubation.

 

 

Brain storming;

Probing questions;

Brief discussion.

  KLB BK IV

Pg 8-9

 

Longhorn Bk IV

Pg 5-6

 

3

Artificial brooding.

Identify requirements for an artificial brooder. Exposition;

Probing questions;

Brief discussion.

  KLB BK IV

Pg 10-11

Longhorn Bk IV

Pg 8-9

 

4

Brooder & brooder management.

Outline management practices of a brooder. Exposition;

Explanations;

 

Artificial brooder. KLB BK IV

Pg 11-13

Longhorn Bk IV

Pg 8-9

 

3

1

Rearing of growers, layers and broilers.

Discuss rearing of growers, layers and broilers. Exposition;

Probing questions;

Brief discussion.

  KLB BK IV

Pg 14

Longhorn Bk IV

Pg 12-13

 

2

Chicken rearing systems.

 

  -Free range rearing

   system.

State factors considered when choosing a rearing system.

Identify requirements for free-range system.

State merits & demerits of free rage system.

 

Q/A & discussion.   KLB BK IV

Pg 15-17

 

Longhorn Bk IV

Pg 13-15

 

3

– Fold system.

Describe fold system.

State merits & demerits of fold systems.

Q/A & discussion. Chicken folds. KLB BK IV

Pg 17-18

Longhorn Bk IV

Pg 15-16

 

4

– Deep liter system.

Describe the requirements for deep liter system of rearing chicks.

State merits & demerits of deep liter systems.

 

Q/A & brief discussion.   KLB BK IV

Pg 18-20

 

Longhorn Bk IV

Pg 16-18

 

4

1

– Battery cage system.

Describe the requirements for battery cage system of rearing chicks.

 

Q/A & discussion. Battery cages. KLB BK IV

Pg 20-21

 

2

Factors affecting egg production.

Vices.

Identify causes of vices such as egg eating and cannibalism and measures taken for the vices. Discussion: causes and control of vices.   KLB BK IV

Pg 23-24

Longhorn Bk IV

Pg 20-21

 

3

Stress.

State causes of stress in birds.

Outline stress management practices.

 

Q/A & discussion.   KLB BK IV

Pg 22-23

Longhorn Bk IV

Pg 20-21

 

4

Culling birds.

Define the term culling.

Give reasons for culling of birds.

Brain storming;

Observing characteristics of a good / bad layer.

Discussion.

 

  Longhorn Bk IV

Pg 20-21

 

5

1

Marketing eggs and chicken meat.

State factors considered in sorting and grading eggs for fresh markets.

Outline methods of killing a bird.

Describe dressing of a bird’s carcass.

Teacher’s demonstrations &  discussion.

 

Topic review questions.

 

  KLB BK IV

Pg 24-27

 

Longhorn Bk IV

Pg 22-23

 

2

LIVESTOCK PRODUCTION (CATTLE)

 

Raising of the young stock.

 

 

 

Explain the importance of feeding calves on colostrum.

Prepare artificial colostrum.

 

 

 

 

Q/A: qualities of colostrum.

Teacher’s demonstration: colostrum preparation.

 

 

 

Artificial colostrums.

 

 

 

KLB BK IV

Pg 28-29

 

Longhorn Bk IV

Pg 25-26

 

3

Methods of calf rearing.

State merits & demerits of natural and artificial methods of calf rearing. Q/A & discussion.   KLB BK IV

Pg 29-30

Longhorn Bk IV

Pg 26-29

 

4

Weaning of calves.

Describe early & late weaning of calves. Q/A, exposition & discussion. Chart –

weaning guide.

KLB BK IV

Pg 30-32

Longhorn Bk IV

Pg 29-30

 

6

1

Rearing replacement stock.

Describe routine management practices for rearing replacement stock.

Give reasons for carrying out varying routine practices.

Q/A: review common management routine practices.

 

Discussion & Q/A. parasite control, castration, disease control, identification, dehorning.

  KLB BK IV

Pg 32-3

 

Longhorn Bk IV

Pg 30

 

2

TEST        

3

Calf housing.

Identify types of calf pens.

Outline requirements for calf pens.

Exposition of new concepts.

Q/A & explanations.

 

Calf houses. KLB BK IV

Pg 33-34

Longhorn Bk IV

Pg 31

 

4

Routine management practices in poultry.

Analyze routine management practices in poultry. Q/A: review routine management practices in livestock.

Brief discussion.

  KLB BK IV

Pg 34-36

Longhorn Bk IV

Pg 31

 

7

1

MILK AND MILKING

Factors affecting milk composition.

 

Highlight factors affecting milk composition.

Brain storming;

Probing questions;

Discussion.

  KLB BK IV

Pg 36-38

Longhorn Bk IV

Pg 32

 

2

Milk secretion and let-down.

Describe the structure of the mammary gland.

Describe the flow of milk from the alveoli to the teat canal.

 

Drawing  and labeling diagram of  the udder.

Exposition of new concepts.

Chart-

Structure of the udder.

KLB BK IV

Pg 38-40

 

Longhorn Bk IV

Pg 33-34

 

3

Clean milk.

State characteristics of clean milk.

Outline essentials of clean milk production.

 

Oral questions & brief discussion.   KLB BK IV

Pg 40-42

Longhorn Bk IV

Pg 34-35

 

4

Milking materials and equipment.

List down necessary milking materials and equipment.

State the purpose of the milking materials and equipment.

 

Brain storming;

Probing questions;

Discussion.

Strip cup. KLB BK IV

Pg 42-44

 

Longhorn Bk IV

Pg 35-37

 

8

1

Milking procedure and technique.

Carry out milking using the correct milking procedure and technique.

Outline rules observed when milking.

 

 

 

Practical activity: milking by hand.

 

Probing questions on milking rules.

 

Lactating cow, basic milking equipment. KLB BK IV

Pg 44-46

 

Longhorn Bk IV

Pg 37

 

2

Dry cow therapy.

 

 

Milk products.

 

Marketing of milk and beef.

Explain the concept of dry cow therapy.

 

Name various milk products.

Describe marketing of milk, beef & their by-products in Kenya.

 

Explanations & brief discussion.   KLB BK IV

Pg 46-47

 

Longhorn Bk IV

Pg 38-40

 

3

FARM POWER & MACHINERY.

 

Sources of power in the farm.

 

 

Describe various sources of power in the farm.

State merits & demerits of each source of power.

 

 

 

 

 

Q/A & discussion: animal power, wind power, waterpower, biogas, solar radiation, and fossil fuel.

   

 

 

KLB BK IV

Pg 50-56

 

Longhorn Bk IV

Pg 42-53

 

4

The tractor:

 

Petrol & diesel engines.

Identify major parts of the tractor petrol & diesel engines.

 

Exposition of new concepts, drawing illustrative diagrams. Chart- petrol engine & diesel engine. KLB BK IV

Pg 57-58

Longhorn Bk IV

Pg 53-54

 

9

1

The four-stroke cycle engine. Describe the four strokes in an engine

State merits & demerits of the four-stroke cycle engine.

 

Exposition of new concepts, drawing illustrative diagrams. Diagrams – The four-stroke cycle. KLB BK IV

Pg 58-61

 

Longhorn Bk IV

Pg 54-55

 

9

2

The two- stroke cycle engine.

 

 

 

Structural and functional differences between petrol and diesel engines.

Describe the two strokes in a cycle.

State merits & demerits of two-stroke cycle engine.

 

State structural and functional differences between petrol and diesel engines.

 

Exposition of new concepts,

drawing; illustrative diagrams;

 

Discussion.

  KLB BK IV

Pg 61-63

 

 

Longhorn Bk IV

Pg 56-57

 

3

Petrol fuel system of a tractor.

Describe the petrol fuel system of a tractor.

State maintenance practices of a petrol fuel system of a tractor.

Block diagram: petrol engine fuel system.

Discussion.

  KLB BK IV

Pg 63-64

Longhorn Bk IV

Pg 60-61

 

4

Diesel fuel system of a tractor.

Describe the diesel fuel system of a tractor.

State maintenance practices of a diesel fuel system of a tractor.

Block diagram: petrol engine fuel system.

Discussion.

  KLB BK IV

Pg 64-65

Longhorn Bk IV

Pg 60-61

 

10

1

Electrical system of a tractor.

Name the components in the electrical system of a tractor.

Highlight methods of maintaining a tractor battery.

Refer to diagram for electrical system of a tractor;

Brief discussion.

Chart – electrical system. KLB BK IV

Pg 65-67

 

Longhorn Bk IV

Pg 61

 

2

Tractor ignition system.

Name the components of tractor ignition system.

Correct some common faults of ignition system.

Discuss maintenance practices of the ignition system.

 

Refer to a diagram for ignition system of a tractor;

Brief discussion.

Chart – ignition system. KLB BK IV

Pg 67-69

 

Longhorn Bk IV

Pg 62-63

 

3

Tractor cooling system.

Briefly describe air-cooled and water-cooled systems.

Discuss proper maintenance of cooling system.

 

Brief discussion. Chart- water cooling system. KLB BK IV

Pg 69-71

 

Longhorn Bk IV

Pg 63-64

 

4

Lubrication system of an engine.

Describe the lubrication system of an engine.

Outline importance of maintaining the lubrication system.

Exposition;

Brief discussion.

  KLB BK IV

Pg 71-72

Longhorn Bk IV

Pg 64-5

   

11

1

Power transmission system of an engine.

Explain the function of power transmission system.

State the function of the clutch, gearbox and the differential.

Teacher exposes the parts of power transmission system.

Refer to diagrams to identify parts of a power transmission system;

Brief discussion.

 

Chart- power transmission

system.

KLB BK IV

Pg 72-76

 

Longhorn Bk IV

Pg 64-65

   

2

Tractor servicing.

Describe tractor servicing and maintenance practices.

 

Brief discussion.   KLB BK IV

Pg 776-77

Longhorn Bk IV

Pg 65-6

   

3

Tractor drawn implements.

Classify tractor drawn implements on basis of attachment to the tractor.

List down maintenance practices for a trailer.

 

Teacher’s explanations.

 

 

Q/A: maintenance practices.

Charts-

Tractor drawn implements.

KLB BK IV

Pg 77-80

 

Longhorn Bk IV

Pg 66-7

   

4

Disc plough. Label parts of a disc plough

List down maintenance practices for a disc plough.

 

Q/A: review primary and secondary cultivation.

 

Drawing labeled diagrams.

 

Q/A & discussion.

Chart- Disc plough

 

KLB BK IV

Pg 79-80

 

Longhorn Bk IV

Pg 68-9

   

12

1

Mould board plough. State operational differences between the disc plough and  mould board plough.

 

  Chart- Mould board plough

 

KLB BK IV

Pg 80-82

Longhorn Bk IV

Pg 70-1

   

2

Harrows.

Identify types of harrows and their uses.

List down maintenance practices for harrows.

 

Drawing diagrams, Q/A & discussion.   KLB BK IV

Pg 82-84

Longhorn Bk IV

Pg 72-77

   

12

3

Other farm implements.

Explain the functional features of subsoilers, ridgers, rotary tillers & mowers.

List down maintenance practices for the

implements.

 

Exposition & brief discussion.

Excursion & exhibitions.

  KLB BK IV

Pg 85-91

 

Longhorn Bk IV

Pg 78-82

   

4

Animal drawn implements.

Identify parts of animal drawn implements and state their functions.

List down maintenance practices for an ox-plough, an ox-plough, and an ox-cart.

State merits & demerits of using animal-drawn implements compared to tractor power.

 

Drawing and labeling an ox-plough;

Probing questions;

Discussion.

Chart:

An ox-plough.

KLB BK IV

Pg 91-94

 

 

Longhorn Bk IV

Pg 82-83

   

END  OF  TERM  ONE  EXAMINATION    

 

SCHEME  OF  WORK               AGRICULTURE  FORM  FOUR                 TERM  ONE  2011    

1

1

AGRIC. ECONOMICS III

(PRODUCTION ECONOMICS)

 

Household firm relationship.

 

Define a household and a firm as business terms.

Describe a household and a firm as producers and consumers and their role in a country’s economic growth.

Q/A: review definition of economics, production economics.

Exposition & explanations.

Q/A & discussion.

 

 

  KLB BK IV

Pg 96-97

 

Longhorn Bk 4

Pg 20-21

   

2

Gross domestic product (GDP) and Gross National product (GNP).

 Per Capita Income.

Define the terms GDP & GNP.

Define the term gross national income (GNI).

 

 

Define the term per capita income.

 

Exposition & explanations.

 

 

 

Calculations.

 

 

  KLB BK IV

Pg 97-98

 

Longhorn Bk 4

Pg 87-88

   

3

Contribution of Agriculture to national development. Explain contribution of Agriculture to development.

 

Brain storming;

Discussion.

  KLB BK IV

Pg 98-9

Longhorn Bk 4

Pg 90-91

   

4

Land as a factor of production.

Describe the economic value of production of crops and livestock and space for construction of farm buildings, agro-industries & infrastructure.

List down methods of land acquisition.

Exposition of new concepts;

Probing questions to elicit responses;

Brief discussion.

  KLB BK IV

Pg 99-100

 

Longhorn Bk 4

Pg 92-3

   

2

1

Labour as a factor of production.

Define the term labour as used in production.

Explain ways of improving labour productivity.

Identify types of labour.

Oral questions & discussion.   KLB BK IV

Pg  100-2

 

Longhorn Bk 4

Pg 93-4

   

2

Capital.

Define the term capital.

Identify types of capital.

List sources of capital.

Oral questions, exposition & discussion.   KLB BK IV

Pg 102-3

Longhorn Bk 4

Pg 94-95

   

3

Management as a production factor.

State functions of a manager in a farm.

Identify good qualities of a manager.

Q/A & discussion.   KLB BK IV

Pg 103-4

   

4

TEST     KLB BK IV

Pg  104-

   

3

1

Production function.

Define production function.

State characteristics of variable and fixed inputs.

Q/A: examples of inputs & outputs; variable and fixed inputs;

Brief discussion.

 

  KLB BK IV

Pg 104-6

Longhorn Bk 4

Pg 96-7

   

2

Production function curves.

Illustrate and interpret input-output relationship graphically. Worked examples: supervised practice. Graph papers. KLB BK IV

Pg 106-7

Longhorn Bk 4

Pg 98

   

3

Increasing returns production functions.

Illustrate and interpret Increasing returns production functions.

Give empirical examples where increasing returns production functions are experienced.

Tabulate inputs and outputs.

Graphical representation of increasing returns production functions.

Graph papers. KLB BK IV

Pg 107-8

Longhorn Bk 4

Pg 99

   

4

Constant returns production functions.

Constant returns production functions.

Give empirical examples where Increasing returns production functions are experienced.

Tabulate inputs and outputs.

Graphical representation of constant returns production functions.

  KLB BK IV

Pg 108-9

 

Longhorn Bk 4

Pg 99

   

4

1

Decreasing returns production functions.

Decreasing returns production functions.

Give empirical examples where decreasing returns production functions are experienced.

Tabulate inputs and outputs.

Graphical representation of decreasing returns production functions.

  KLB BK IV

Pg 109-10

   

2

Law of diminishing returns.

State the law oh diminishing returns. Refer to illustrative tables.

Plot graphs from the tables;

Discuss shape of the curve.

  KLB BK IV

Pg 112

 

Longhorn Bk 4

Pg 100-1

   

3

Zones of a PF curve.

Divide a production function into three zones.

Identify rational zones of production.

Q/A: review AP, MP.

Guided discovery of the three zones.

Chart –

Curve showing 3 zones of PF.

KLB BK IV

Pg 113-5

Longhorn Bk 4

Pg 101-2

   

4

The principles of substitution.

 

 

Input-input relationship.

State the principles of substitution.

Give examples illustrating principles of substitution.

Identify ways of combining inputs.

Exposition.

 

Illustrative examples, brief discussion.

  KLB BK IV

Pg 115-6

 

Longhorn Bk 4

Pg 102

   

5

1

Product-product relationship.

 

Supplementary and complementary products.

 

Give examples of product-product relationship.

 

Give illustrative examples depicting supplementary and complementary products.

Oral questions: joint products, competitive products.

 

Discussion.

  KLB BK IV

Pg 116-7

 

Longhorn Bk 4

Pg 103

   

2

The principle of equi-marginal returns.

 

The concept of cost.

State the principle of equi-marginal returns.

 

Determine the cost of production.

Identify the role of cost in production.

List types of costs.

Discussion.

 

 

Exposition;

Worked examples.

  KLB BK IV

Pg 117-9

 

Longhorn Bk 4

Pg 104-5,6

   

3

Types of revenue.

Compute total revenue, net revenue and marginal revenue given the relevant information. Worked examples;

Explanations.

  KLB BK IV

Pg 119-120

Longhorn Bk 4

Pg 107

   

4

Farm planning.

State factors to consider when drawing a farm plan. Exposition, Q/A & discussion.   KLB BK IV

Pg 121-2

Longhorn Bk 4

Pg 108

   

6

1

Making a farm plan.

Outline steps followed in making a farm plan. Exposition, probing questions & discussion.   KLB BK IV

Pg 122-3

Longhorn Bk 4

Pg 109

   

2

Farm budgeting.

Define a farm budget.

Analyse importance of farm budgeting.

Exposition & discussion.   KLB BK IV

Pg 123

Longhorn Bk 4

Pg 110

 

   

3

Types of farm budgets.

Describe types of farm budgets.

Give examples of contexts where certain types of budgets are used.

Draw a partial budget.

Draw a complete budget.

 

Exposition & discussion,

Worked examples;

Supervised practice;

Written exercises.

  KLB BK IV

Pg 124-7

 

Longhorn Bk 4

Pg 110-1

   

4

Farmer’s support services

Extension, training & banking.

 

Describe extension, training & banking as support services to the farmers.

 

Exposition & explanations.   KLB BK IV

Pg 127-8

 

Longhorn Bk 4

Pg 112-3

   

7

1

Credit.

 

 

 

Sources of credit.

 

 

Define the term credit.

Identify types of credit.

Differentiate between hard & soft credit.

List down sources of credit.

Identify problems associated with credits.

 

Detailed discussion

& exposition of new concepts.

  KLB BK IV

Pg 128-130

 

 

 

Longhorn Bk 4

Pg 113-5

   

2

Artificial insemination

&

Agricultural research.

Describe A.I. services provided to farmers.

Identify objectives of Agricultural research.

Give examples of Agricultural research centers in Kenya.

 

Detailed discussion

& exposition of new concepts.

  KLB BK IV

Pg 130-2

 

Longhorn Bk 4

Pg 115-6

   

3

Marketing.

 

Farm input suppliers

Tractor hire service

Cite examples of organizations that help farmers in marketing their produce.

Cite organizations where farmers can obtain farm inputs.

State merits & demerits of tractor hire service.

Cite points of tractor hire service.

Writing initials in full e.g. KPCU.

 

Brief discussion

  KLB BK IV

Pg 132-4

 

 

Longhorn Bk 4

Pg 112-3

 

   

4

Risks and uncertainties in farming.

Define the terms risk and uncertainty.

List types of risk and uncertainties.

 

 

 

Brain storming;

Detailed discussion.

  KLB BK IV

Pg 134-5

 

Longhorn Bk 4

Pg 116-7

   

8

1

Adjusting to uncertainties and risks. Outline ways of adjusting to risks and uncertainties.

 

 

 

Brain storming;

Detailed discussion.

  KLB BK IV

Pg 135-6

 

Longhorn Bk 4

Pg 118-9

   

2

AGRICULTURE ECONOMIC IV (FARM ACCOUNTS)

 

Financial documents.

 

 

 

 

 

Outline details contained in an invoice, receipt, delivery note and a purchase order.

 

 

 

 

Oral questions & brief discussion.

 

 

 

Invoice, receipt, delivery note and a purchase order.

 

 

 

 

KLB BK IV

Pg 139-145

 

Longhorn Bk 4

121

 

 

3

Books of accounts.

Describe features of the ledger and the inventory. Oral questions & brief discussion.

Illustrative tables.

  KLB BK IV

Pg 146-150

Longhorn Bk 4

Pg 124

 

4

Cash book.

Describe features of the cash book.

Balance cash book.

Oral questions & brief discussion.

Illustrative examples.

 

Cash book. KLB BK IV

Pg 150

Longhorn Bk 4

Pg 125

 

9

1

Journal

&

Subsidiary books of the Journal.

Describe features of the journal & subsidiary books of the journal. Oral questions & brief discussion.

Illustrative tables.

  KLB BK IV

Pg 151-3

 

2

 

 

 

Financial statements.

Balance sheet.

Describe features of balance sheets.

Prepare a balance sheet.

 

 

Make entries in a balance sheet.

Prepare a balance sheet.

Supervised practice.

Balance sheet. KLB BK IV

Pg 154-7

Longhorn Bk 4

Pg 129-130

 

3

Solvency of a business.

Determine whether a business is solvent or insolvent.

 

    KLB BK IV

Pg 154-7

Longhorn Bk 4

Pg 130

 

4

Profit and loss account.

Define a profit and loss account.

Draw a profit and loss A/C.

Compute net profit.

 

Teacher gives format of profit and loss A/C.

Worked examples.

Supervised practice.

  KLB BK IV

Pg 157-9

Longhorn Bk 4

Pg 132-3

 

10

1,2

Cash analysis.

Define the term cash analysis.

Draw a cash analysis.

Compute total receipt and total expenditure for a given accounting period.

Worked examples.

Supervised practice.

Written exercise.

  KLB BK IV

Pg 159-162

 

Longhorn Bk 4

Pg 133-4

 

3

AGRICULTURAL MARKETING & ORGANIZATIONS

 

Market and marketing.

 

 

 

 

 

 

 

 

 

Define the term market as an institution.

Distinguish between a perfect and imperfect market.

 

 

 

 

 

Q/A: definition.

Teacher’s explanations.

   

 

 

 

KLB BK IV

Pg 164

 

Longhorn Bk 4

Pg 137

 

4

Types of markets.

 

Monopoly.

Oligopoly

     &

Monopsony.

 

Identify features of a monopolistic competition in a market, oligopolistic and monopsonistic markets.

 

Brain storming;

Exposition;

Discussion.

  KLB BK IV

Pg 165-6

 

Longhorn Bk 4

Pg 137-8

 

11

1

Price theory and demand.

Define the terms price & demand.

Sketch the demand curve.

Explain the term demand schedule.

Exposition;

Curve sketching & explanations.

  KLB BK IV

Pg 166-8

Longhorn Bk 4

Pg 139-140

 

2

Factors affecting demand for a commodity.

Outline factors affecting demand for a commodity. Q/A, discussion & explanations.   KLB BK IV

Pg 168-9

Longhorn Bk 4

Pg 140-2

 

3

Elasticity of demand.

Explain the concept of elasticity of demand.

Illustrate demand for a commodity.

Calculate elasticity of demand.

Identify types of elasticity of demand.

Illustrate elastic, inelastic  & unitary demand graphically.

Teacher’s explanations.

Graphical illustration.

 

Worked examples. Supervised practice.

 

 

 

Graphical representation of demand.

  KLB BK IV

Pg 170-3

 

 

Longhorn Bk 4

Pg 142-4

 

4

Factors affecting elasticity of demand.

State factors affecting elasticity of demand. Exposition;

Explanations.

  KLB BK IV

Pg 173-4

 

 

12,

13

END  OF  TERM TWO EXAMINATIONS    

 

FORM             FOUR            AGRICULTURE      TERM            THREE    2011  

1

1

Supply

&

Supply-price relationship.

Define the term supply.

Illustrate supply-price relationship.

Sketching supply-price curves.

Refer to supply schedules.

Discussion.

  KLB BK IV

Pg 174-5

Longhorn Bk 4

Pg 144-5

 

2

Factors affecting supply of a commodity.

State & explain factors affecting supply of a commodity. Q/A & detailed discussion.   KLB BK IV

Pg 175-7

Longhorn Bk 4

Pg 145-6

 

3

Elasticity of supply (Es).

Define elasticity of supply (Es).

Calculate (Es)

Q/A: review Ed hence defines Es.

Worked examples.

Supervised activity.

  KLB BK IV

Pg 177-8

Longhorn Bk 4

Pg 147

 

4

Determination of market prices.

Explain how market prices are determined.

Determine the equilibrium or market prices of a commodity in a free market.

 

Teacher’s explanation.

 

Q/A : review demand and supply curves.

Plot both curves.

Interpret the graphs.

  KLB BK IV

Pg 178-9

 

Longhorn Bk 4

Pg 149

 

2

1

 

 

 

Price control.

 

 

Marketing and marketing function.

Explain the role of government in price control.

 

Define marketing and marketing function.describe tingfunction. a market.

Brain storming;

Exposition;

Discussion.

  KLB BK IV

Pg 179-183

 

Longhorn Bk 4

Pg 151

 

2

Marketing organizations and agencies.

 

Wholesalers & retailers.

 

 

 

Explain the arbitrage role of a wholesaler.

Identify services provided by retailers.

 

 

 

Brain storming;

Exposition;

Discussion.

   

 

KLB BK IV

Pg 183-4

 

Longhorn Bk 4

Pg 151

 

 

3

Itinerant traders, broker agents & commission agents.

Outline the functions of Itinerant traders, broker agents & commission agents in a market. Exposition & explanation.   KLB BK IV

Pg 184-5

 

 

 

 

4

Packers and processors, marketing boards & auctioneers.

Outline functions of packers and processors, marketing boards & auctioneers in a market. Q/A & detailed discussion.   KLB BK IV

Pg 185-6

 

3

1

Special characteristics of Agricultural products.

Describe bulkiness, weight, volume, seasonality and perishability of Agricultural products. Oral questions & detailed discussion   KLB BK IV

Pg 186-8

 

2

Agricultural organizations.

Kenya sugar authority, Horticultural crops Development Authority, AFC, ADC, and KMC.

 

 

Outline the functions of Kenya sugar authority, Horticultural crops Development Authority, AFC, ADC, and KMC. Probing questions,

Brief discussion

  KLB BK IV

Pg 189-192

 

Longhorn Bk 4

Pg 163-4

 

3

Other Farmers’ Associations:

 KNFU, ASK, 4K-club, YF club.

Outline the functions of other Farmers’ Associations such as KNFU, ASK, 4K-club, YF club. Probing questions,

Brief discussion

Assignment.

  KLB BK IV

Pg 195-7

 

4

Co-operative societies.

Outline the principles of co-operatives.

Highlight functions of co-operatives.

 

Probing questions, brief discussion, & teacher’s explanations.   KLB BK IV

Pg 161-2

 

4

1

AGROFORESTRY

Definition of

agroforestry.

 

Forms of agroforestry.

 

 

Define the term agroforestry.

 

Describe forms of agroforestry.

 

 

 

Probing questions & explanations.

  KLB BK IV

Pg 200-1

 

Longhorn Bk 4

Pg 166-7

 

2

Importance of agroforestry.

Explain the importance of agroforestry.     KLB BK IV

Pg 201-2

Longhorn Bk 4

Pg 167-8

 

3

Tree nursery.

State factors considered when selecting the nursery site.

Describe treatment of nursery seeds.

 

 

Q/A & discussions. Tree nurseries. KLB BK IV

Pg 203-5

 

Longhorn Bk 4

Pg 169-173

 

4

Nursery management practices

    &

Care and management of trees.

Identify practices carried out on the nursery in order to produce healthy tree seedlings.

Describe the care and management of trees.

Brain storming;

Discussion;

Practical activities – transplanting seedlings.

Tree nurseries. KLB BK IV

Pg 205-8

 

Longhorn Bk 4

Pg 173-177

 

 

SUMMATIVE ASSESSMENT TEST

 

       

 

Maranda High KCSE Exam Papers Plus Marking Schemes (All Subjects)

Maranda High KCSE Exam Papers Plus Marking Schemes (All Subjects)

2023 Maranda Pre-Mock AGRIC PP2 MS.pdf
2023 Maranda Pre-Mock AGRIC PP2 MS (2).pdf
2023 Maranda Pre-Mock AGRIC PP2 QNS (2).pdf
2023 Maranda Pre-Mock AGRIC PP2 QNS.pdf
2023 Maranda Pre-Mock BIOPP1MS (2).pdf
2023 Maranda Pre-Mock BIOPP1MS.pdf
2023 Maranda Pre-Mock BIOPP1QNS (2).pdf
2023 Maranda Pre-Mock BIOPP1QNS.pdf
2023 Maranda Pre-Mock BIOPP2MS (2).pdf
2023 Maranda Pre-Mock BIOPP2MS.pdf
2023 Maranda Pre-Mock BIOPP2QNS (2).pdf
2023 Maranda Pre-Mock BIOPP2QNS.pdf
2023 Maranda Pre-Mock BIOPP3MS (2).pdf
2023 Maranda Pre-Mock BIOPP3MS.pdf
2023 Maranda Pre-Mock BIOPP3QNS (2).pdf
2023 Maranda Pre-Mock BIOPP3QNS.pdf
2023 Maranda Pre-Mock BUSS PP2 MS (2).pdf
2023 Maranda Pre-Mock BUSS PP2 MS.pdf
2023 Maranda Pre-Mock BUSS PP2 QNS (2).pdf
2023 Maranda Pre-Mock BUSS PP2 QNS.pdf
2023 Maranda Pre-Mock CHEM PP1 MS (2).pdf
2023 Maranda Pre-Mock CHEM PP1 MS.pdf
2023 Maranda Pre-Mock CHEM PP1 QNS (2).pdf
2023 Maranda Pre-Mock CHEM PP1 QNS.pdf
2023 Maranda Pre-Mock CHEM PP2 MS (2).pdf
2023 Maranda Pre-Mock CHEM PP2 MS.pdf
2023 Maranda Pre-Mock CHEM PP2 QNS (2).pdf
2023 Maranda Pre-Mock CHEM PP2 QNS.pdf
2023 Maranda Pre-Mock CHEM PP3 MS (2).pdf
2023 Maranda Pre-Mock CHEM PP3 MS.pdf
2023 Maranda Pre-Mock CHEM PP3 QNS (2).pdf
2023 Maranda Pre-Mock CHEM PP3 QNS.pdf
2023 Maranda Pre-Mock CHEMISTRY PP3 CONFIDENTIAL (2).pdf
2023 Maranda Pre-Mock CHEMISTRY PP3 CONFIDENTIAL.pdf
2023 Maranda Pre-Mock CHEMPP3MS (2).pdf
2023 Maranda Pre-Mock CHEMPP3MS.pdf
2023 Maranda Pre-Mock COMPPP1QNS (2).pdf
2023 Maranda Pre-Mock COMPPP1QNS.pdf
2023 Maranda Pre-Mock COMPPP2QNS (2).pdf
2023 Maranda Pre-Mock COMPPP2QNS.pdf
2023 Maranda Pre-Mock CREPP2QNS (2).pdf
2023 Maranda Pre-Mock CREPP2QNS.pdf
2023 Maranda Pre-Mock ENG PP3MS (2).pdf
2023 Maranda Pre-Mock ENG PP3MS.pdf
2023 Maranda Pre-Mock ENGPP1MS (2).pdf
2023 Maranda Pre-Mock ENGPP1MS.pdf
2023 Maranda Pre-Mock ENGPP1QNS (2).pdf
2023 Maranda Pre-Mock ENGPP1QNS.pdf
2023 Maranda Pre-Mock ENGPP2MS (2).pdf
2023 Maranda Pre-Mock ENGPP2MS.pdf

Download Form 1 to 4 Free End Term 3, End Year Exams

Form 1 to 4 Free End Term 3, End Year Exams

BUS F2.pdf
F1 AGRIC END TERM 3 EXAMS.pdf
F1 BIO END TERM 3 EXAMS.pdf
F1 BUSS END TERM 3 EXAMS.pdf
F1 CHEM END TERM 3 EXAMS.pdf
F1 CRE END TERM 3 EXAMS.pdf
F1 ENG END TERM 3 EXAMS.pdf
F1 GEO END TERM 3 EXAMS.pdf
F1 HIST END TERM 3 EXAMS.pdf
F1 KIS END TERM 3 EXAMS.pdf
F1 MATHS END TERM 3 EXAMS.pdf
F1 PHY END TERM 3 EXAMS.pdf
F2 AGRIC END TERM 3 EXAMS.pdf
F2 BIO END TERM 3 EXAMS.pdf
F2 CHEM END TERM 3 EXAMS.pdf
F2 CRE END TERM 3 EXAMS.pdf
F2 ENG END TERM 3 EXAMS.pdf
F2 GEO END TERM 3 EXAMS.pdf
F2 HIST END TERM 3 EXAMS.pdf
F2 KISW END TERM 3 EXAMS.pdf
F2 MATH END TERM 3 EXAMS.pdf
F2 PHY END TERM 3 EXAMS.pdf
F3 AGRIC END TERM 3 EXAMS.pdf
F3 BIO END TERM 3 EXAMS.pdf
F3 BUSS END TERM 3 EXAMS.pdf
F3 CHEM END TERM 3 EXAMS.pdf
F3 CRE END TERM 3 EXAMS.pdf
F3 ENG END TERM 3 EXAMS.pdf
F3 GEO END TERM 3 EXAMS.pdf
F3 HIST END TERM 3 EXAMS.pdf
F3 KISW END TERM 3 EXAMS .pdf
F3 MATHS END TERM 3 EXAMS.pdf
F3 PHY END TERM 3 EXAMS.pdf

NEWTON’S LAWS OF MOTION PHYSICS NOTES

Chapter Three

NEWTON’S LAWS OF MOTION

Newton’s First Law

Newton’s first law, which states that a body remains in its state of rest or uniform motion in a straight line unless acted upon by an external force

Inertia

The property of bodies to resist change in state of motion is called inertia and it explains why cars have seat belts

Newton’s first law of motion suggests that matter has an in-built reluctance to change its state of motion or rest.

When a moving bus comes to an abrupt stop, the passengers lurch forward, i.e., tends to keep on moving. Likewise, when a bus surges forward, the passengers are jerked backwards, i.e., tend to resist motion. This property of bodies to resist change in state Of motion is called inertia and it explains why cars have seat belts

The mass of a body is a measure of its inertia. A larger mass requires a larger force to produce
a given acceleration or deceleration on it than a smaller mass. The larger mass therefore has a
greater inertia.

Newton’s first law of motion is also referred to as the law of inertia.

Momentum’

A heavy-commercial vehicle requires a greater tractive force to start it moving when loaded than when empty. Likewise, a greater braking force is needed to bring to rest a heavy commercial vehicle than a small passenger car travelling at the same velocity. The vehicles each have a quantity called momentum which depends on the mass and the velocity of the vehicle. In the foregoing illustration, the heavy commercial vehicle has a greater momentum than the small car.

The momentum of a body is defined as the product of its mass and velocity. If m is the mass of a body in kg and v Its velocity in ms”, then;

momentum = mass (kg) x velocity (ms-1)

= mv

The SI unit of momentum is therefore kgms-1. Momentum is a vector quantity, having both magnitude and direction. The direction of momentum is same as that of velocity of the body.

Example 1

A van of mass 3 metric tonnes is travelling at a velocity of 72 kmh-1. Calculate the momentum of the vehicle.

 

Example 2

A car is moving at 36 kmh-1. What velocities will double its momentum?

 

Newton’s Second Law

Newton’s second law of motion states that the rate of change of momentum of a body is’ directly proportional to the resultant external force producing the change, and takes place in the direction of the force. Thus; resultant force acting  rate of change of momentum.

If the forces acting on the body are in equilibrium (balanced), then the resultant force acting on the body is zero, hence no change in momentum. This implies that the body under this condition will continue in its state of rest or uniform motion in a straight line (Newton’s first law).

Relation between Force, Mass and Acceleration

Consider a force F acting on a body of mass m for a time t. If its velocity changes from u to v, then;

 

 

change in momentum = final momentum – initial momentum
= mv-mu

 

:. Rate of change of momentum=

But acceleration a=

Hence, F mass x acceleration
So, F = krna, where k is a constant.

The Newton is that force which produces an acceleration of 1 ms-2 when it acts on a mass of 1 kg.
This definition gives; F = 1 N, a = 1 ms-2 and m = 1 kg.

Hence, substitution in F = kma leaves k = 1.

:. F=ma

Newton’s second law of motion can be verified by measuring the acceleration produced when various forces are applied to a frictionless trolley running on a friction-compensated runway. The trolley is taken to be of unit mass and the applied force is measured using identical elastic cords by taking the tension of the cord as a unit force when stretched by a certain
length.

Example 3

What is the mass of an object which is accelerated at 3 ms-2 by a force of 125 N

Example 4

A truck weighs 1.0 x 105N and is free to move. What force will give it an acceleration of 1.5 ms-2? (Take g = 10 Nkg-l)

Example5

A trolley of mass 1.5 kg is pulled along by an elastic cord and given an acceleration of2 ms-2. Find the frictional force acting on the trolley if the tension in the cord is 5 N.

Example 6

A car of mass 1 200 kg travelling at 45 ms-1 is brought to rest in 9 seconds. Calculate the average retardation of the car and the average force applied by the brakes.

 

Impulse

When a force acts on a body for a very short time, the force is referred to as an impulsive force.
The result produced is known as the impulse of the force. Impulsive forces occur when two moving bodies collide, e.g., when two cars collide head-on or when a hammer strikes a stationary metal plate.

If a force F acts on a body of mass m for a time t, then the impulse of the force or impulse is given by force x time.

That is, impulse = force x time
= Ft

From Newton’s second law;

F=

This can be rewritten as; Ft = mv – mu

Since mv – mu is the change in momentum produced in the body during the time t, the impulse of a force acting on a body during a given time interval is equal to the change in momentum produced in the body in that time.

The SI unit of impulse is Newton second (Ns).

Therefore, another unit of momentum is the Newton-second (Ns). Since the rate of change of momentum is equal to impulse, i.e., Ft = p,
F = /t. Thus, force can be defined as rate of change of momentum.

A plot of force F against time is as in figure 3.9. The area under the curve is Ft or change in momentum during collision.

 

 

 

Large impulsive force are produced when momentums of bodies change within a very short time.

For example, when the velocity of a car is suddenly brought down to zero in a collision, the impulsive force on the passengers is so great that it could be fatal.

Seat-belts and airbags help in safeguarding against severe injuries occasioned by inertial forward surge.

The same applies to collapsible bumpers and steering which also helps during head on collisions by cushioning impulsive forces during head-on collisions through collapsing.

Example 7

The graph in figure 3.10 shows the force on a tennis ball when served during a game. Find the mass of the racket with a velocity of 40 ms-1 (Assume the ball is stationary before it is struck)

 

 

 

 

Example 8

(a) Determine the change in momentum produced when a force of3.5 x 103 N acts on a body which is at rest for 0.02 seconds.

 

(b) What velocity will be given to the body if it has a mass of 20 kg?

Example 9

 

The valve of a gas cylinder containing 15 kg of compressed gas is opened and the cylinder empties in 1 hour and 20 minutes. If the gas issues from the exit nozzle with an average velocity of 30 ms -1, find the force exerted on the cylinder.

Example 10

A truck of mass 2 000 kg starts from rest on horizontal rails. Find the speed 3 seconds after starting if the tractive force by the engine is 1 000 N.

 

Example 11

A ball of mass 35 g travelling horizontally at 20 ms-1 strikes a wall at right angles and rebounds with a speed of 16 ms-1. Find the impulse exerted on the ball.

 

Newton’s Third Law

 

Newton’s third law of motion states action and reaction are equal and opposite.

The law tells us that forces do not occur singly but due to action and reaction, they occur in pairs.

As the floor is part of a large mass (earth), the acceleration produced on it is not noticeable.

The force due to gravity W is the action force while that acting normally upwards is the reaction
force R. Since there is no resultant motion;

R=W=mg

Note:

The action force is produced by the block of wood when its weight is exerted on the table. The reaction is the equal force exerted by the table top on the block of wood. Hence. ‘action always begs for a reaction!’

 

Weight of a Body in a Lift

 

A passenger in a lift (elevator) experience forces against the feet, depending on the direction of motion and the acceleration of the lift. Consider a body of mass m on a weighing machine in a lift.

LAW OF CONSERVATION OF LINEAR MOMENTUM

The law of conservation of linear- momentum, which states that for a system of colliding bodies, the total linear momentum remains constant, provided no external forces act

Example 14

 

A body A of mass 5 kg moving with a velocity of 3 ms-1 collides head-on with another body B of mass 4 kg moving in the opposite direction at 6ms-1. If after the collision the bodies move together (coalesce), calculate the-common velocity v.

Example 15

A bullet of mass 0.005 kg is fired from a gun of mass 0.5 kg. If the muzzle velocity bullet is 350 ms-1, determine the recoil velocity of the gun.

 

Collisions

 

One common property of any system of colliding bodies that the total momentum is conserved.
After collision, bodies may:

 

(i) fuse and move together in one direction, .
(ii) separate and move in different directions, or,
(iii) separate and move in the same direction.

Elastic Collisions

An elastic collision is one in which both kinetic energy and momentums are conserved.

 

Inelastic Collisions

 

An inelastic collision is one in which momentum is conserved but kinetic energy is not. The collision of lumps of plasticine or a bullet fired from a gun getting embedded into a block is cases of perfectly inelastic collisions. The characteristic of this type of collision is that after the collision:

(i) the total mass is the sum of the masses of the individual bodies.
(ii) the bodies end up with a common velocity.

In inelastic collisions, kinetic energy is lost because the bodies undergo some deformation.
Also, some of the energy is transformed to heat, sound or light.

Example 16

 

A bullet of mass 10 g travelling horizontally at a speed of 100 ms -1 embeds itself in a block of wood of mass 990 g suspended from a light inextensible string so that it can swing freely.
Find:

(i) the velocity of the bullet and block immediately after collision.
(ii) the height through which the block rises.

Example 17

A minibus of mass 1 500 kg travelling at a constant velocity of  72 kmh-1 collides with a stationary car of mass 900 kg. The impact takes 2 seconds before the two move together at a constant velocity for 20 seconds. Calculate:

(a) the common velocity.

(b) the distance moved after the impact.
(c) the impulsive force.

(d) the change in kinetic energy.

 

 

 

 

 

 

 

Some Applications of the Law of Conservation of Momentum
Rocket and Jet Propulsion

A rocket propels itself forward by forcing out its exhaust gases. The hot exhaust gases are pushed out of the exhaust nozzle at high velocity and gain momentum in one direction. The rocket thus gains an equal momentum in the opposite direction. The rate at which the momentum changes provides the forward thrust on the rocket.

Note:

The rocket engine uses liquid hydrogen as its fuel and ‘liquid oxygen for combustion. It moves faster in the outer space, where there is no air resistance, than in the earth’s atmosphere.

A jet engine works on the same principle as the rocket engine but requires air which provides oxygen for combustion. The jet engine also requires a large mass of air to push out of  its exhaust nozzles, so as to provide greater thrust.

The Garden Sprinkler

The garden sprinkler operates on the same principle as the engine discussed above. The pressure ;’ of the water in the pipe causes the water to be ejected through the nozzles at high velocity. The ejected water gains momentum and causes the sprinkler to rotate as in figure 3.24.

 

 

 

 

FRICTION

Friction is the resistance a body experience when it tend to move over another body

Static/ limiting friction is the maximum force between the surfaces before a body start moving

Sliding/ dynamic friction is the maximum force between the surfaces when the body is in motion

Molecular Explanation of Friction

smooth surfaces would look very rough when viewed under a powerful microscope.
This is due to some molecules on the surface lying on top of one another forming ‘tiny hills’.
The pressure at these points is quite enormous and the molecules making the ‘tiny hills’ which are in contact tend to stick together

For the bodies to move over each other work has to be done to overcome the interlocking between the ‘bumps’ and the ‘troughs’. The force opposing the work being done constitutes friction.

 

Laws of Friction

Experimental results on friction between solids are summed up under the following laws:
(i) Frictional force between two surfaces oppose their relative motion.

(ii) Frictional force is independent of the area of contact of the given surfaces when the normal reaction is constant.

(iii) . Frictional friction is directly proportional to the normal reaction R.
(iv) Kinetic friction is independent of relative velocity.

(v) Frictional force is dependent on the nature of the surfaces in contact.

From the third law above,

F

F=

Where  is the coefficient of friction

NB RESULTANT FORCE = FORCE APPLIED – FRICTION

Resultant force causes the body to accelerate

Example 18

A wooden box of mass 30 kg rests on a rough floor. The co-efficient of friction between the floor and the box is 0.6.

(a) Calculate the force required to just move the box.

(b) If a force of200 N is applied to the box, with what acceleration will it move? (Take g = 10 ms-2)

 

 

Example 19

A block of metal with a mass of 20 kg requires a horizontal force of 50 N to pull it with uniform velocity along a horizontal surface. Calculate the co-efficient of friction between the surface and the block. (Take g = 10 ms-2)

Methods of Minimising Friction

 

It may not be possible to achieve a completely frictionless surface, but friction can be greatly minimized using the following:

Rollers

 

Rollers are placed between two rough surfaces so that when one body is to slide, friction is reduced. Rollers may be placed between the floor and heavy crates to enable the crates to slide,

Rollers may also be used when a marine vessel is being launched. They work on the principle that rolling friction is less than sliding friction.

Ball Bearings

Ball bearings reduce the friction for rotating axles. They are used extensively in machinery and are made of hard steel to prevent wear

Grease must be used together with ball bearings to lubricate the rolling action.

 


Lubrication

This is the application of oil or grease between moving parts.

Air Cushion

 

Air cushioning is done by blowing air into the space between surfaces. This prevents the surface coming into contact. The hovercraft uses air cushion to move with greatly reduced frictional force. Also air cushion is used in air tracks to produce a frictionless runway

Applications of Friction
Walking

Walking is made easier by friction. Pavements are made rough and tyres treaded to increase friction.

Motor Vehicles

Rotating tyres push backwards against the road surface. Friction opposes this force and the resultant force enables the vehicle to move.

Brakes

Friction between the brake drum and the brake lining halts the vehicle.

Matchstick

Friction between the matchstick head and the rough surface develops heat, igniting the stick head.

Friction can also be a nuisance. It causes wear, tear and noise between moving parts of a system, hence the need for lubrication in machines. Friction also, causes energy loss since work has to be done against it.

VISCOSITY

It is more difficult to wade through water than to move the same distance in open air space.
A steel ball dropped in a cylinder full of glycerine takes longer to reach the bottom than when dropped into the cylinder full of water.

This frictional resistance to motion in fluids is called viscosity. It is defined as the force which opposes the relative motion between the layers of the fluid. Glycerine has higher viscosity than water.

Terminal Velocity

EXPERIMENT 3.5: To investigate the relationship between the viscous drag F and velocity v
Apparatus

Tall measuring cylinder (1 000 ml), ball bearing, glycerine, stop watch, metre rule, rubber bands.

 

 

 

 

 

 

 

 

 

Procedure

  • Fill the measuring cylinder with glycerine.
  • Fix narrow horizontal rubber bands labelled 1, 2, 3,4, 5 and 6 at equal intervals along the cylinder, as shown in figure 3.33.
  • Introduce a small ball bearing gently into the liquid (first dip the ball into glycerine).
  • Measure the time of fall from the surface to the band labelled 1.
  • Repeat for bands 2, 3, 4, 5 and 6.
  • Determine the time of fall between each pair of rubber bands, i.e., between land 2, 2 and 3,3 and 4, 4 and 5, and, 5 and 6.
  • Determine the velocity for each pair of bands and record the results in table 3.5.

Table 3.5

 

TIme of Distance between TIme between Velocity between
.fall to bands bands bands
level      
1 =      
2 = 1 and 2    
3 = 2 and 3    
4 = 3 and 4    
5 = 4and5    
6 = 5 and 6    
  • Plot a graph of velocity against time of fall.

Observation

The ball bearing moves with increasing velocity when released into the liquid. The velocity of the ball between bands 4, 5 and 6 appears not to change.

A plot of velocity against time is as shown in figure 3.34.

 

 

Explanation

The forces acting on the ball when it is moving in a liquid are:
(i) its weight mg, acting vertically downwards.

(ii) the viscous drag F due to the liquid, acting vertically upwards.
(iii) the upthrust U due to the liquid, acting vertically upwards.
These forces are shown in figure 3.35.

When the ball enters into the liquid, mg > F + U and the resultant downward force therefore accelerates the ball towards the bottom of the cylinder. The viscous drag F however increases with the velocity and soon mg becomes equal to upward force (F + U). The resultant force is now zero and the ball attains a steady velocity called terminal velocity vto The terminal velocity is the constant velocity attained when the sum of the upward forces equals the weight of the object falling in the fluid.

A plot of velocity against time for a body falling through different liquids is shown in figure 3.36.

 

 

 

 

 

 

 

 

Stokes’Law

Stokes established that when a small object such as a steel sphere of radius r is dropped through a column of liquid and moves with a velocity v, it experiences a force which is directly proportional to:

(i) the radius r of the sphere.
(Ii) the velocity v of the sphere.

So, F  rv. Hence, F = krv, where k is a constant.

Stokes found that k=6 where 11 is called the co-efficient of viscosity.
:. F = 6

This is the expression for Stokes’ law. The law holds when:

(i) the radius of the ball is small compared to the extent of liquid surface.
(ii) the ball does not create turbulence in the liquid as it falls.