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E nergy And Its Sources

To perform any work, we need energy. Energy is the capacity to do work.

Energy has various forms such as electrical, heat, mechanical, sound, light atomic

and chemical energy. It can be converted from one form to another.

Heat Energy
Magnetic Energy
Light
Electrical Energy
Chemical Energy Sound Energy

We get energy from food but machines use energy Factual Study
from fuel, such as petrol, diesel, etc. The amount of energy Americans

The natural sources of energy are: use doubles every 20 years.

Solar Energy : The energy which we get from the sun is called solar energy. Sun
is the ultimate source of energy. Solar heaters and solar cookers are devices which
we use with the help of solar energy. Green plants use solar energy to prepare the

food that we eat.

Solar heater Solar cooker

Wind Energy : The energy we get from moving air is called wind energy. To
generate electricity and to draw underground water we use windmills.

Wind mill Wind farm

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