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Magnetic Force
When we bring a magnet near an iron object. The magnet
attracts the iron object towards itself. This is because of
magnet has a force called magnetic force.

Work Magnet attracting
iron objects

When you apply force to move any object, you do work. When you pull a chair, you do

work. You read, play, fly kite, wear clothes etc. all these are work. But, when you push

an almirah and it is not pushed, no work is done. Thus, work is done when force is

applied on an object and it moves.

A boy pulling chair A girl reading farmer ploughing the field

Energy

Energy is the ability to do work. Only a body which has energy in it can produce a force
to carry out work. Energy is not produced. It just changes from one form to another
form. For example, coal contains chemical energy stored in it. When we burn it, we get
heat and light energy. The heat is then converted into electric energy and so on. Thus
energy just changes its forms.

HEAT ENERGY LIGHT ENERTY SOUND ENGERY ELECTRICAL ENERGY

Sun is the main source Sun is the main source T.V., radios, speakers, This energy is used to

of heat. This energy is of light. Fuels on music systems are run appliances like T.V.,

also produced when burning also produce s o u rc e s o f s o u n d microwave, washing

fuels like wood, coal, light energy. energy. machine, etc.

etc. are burnt.

There are many types of energy. Like heat energy, kinetic energy, potential energy,
light energy, mechanical energy, solar energy etc. Solar energy that we get from the

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