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Question
Explain conservation of energy.
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Solution
Energy cannot be created cannot be destroyed also. It is changed from one form to another form or transferred from one object to another object. Examples for conservation of energy in our daily life are:
-
Water dam:
a. Water stored in water dams possesses potential energy.
b. When water falls down, the potential energy of water is converted, into kinetic energy.
c. Kinetic energy of water rotates the turbines and electric energy is generated. - Electrical appliances:
a. Electrical energy is used in many domestic appliances such as electric stoves, iron boxes, and fans.
b. Electric energy flows into the coil in the devices.
c. As the current flows, it heats up the coil.
d. With the help of this heat energy, we do many useful works.
e. Thus, electrical energy is converted into heat energy.
f. Electical energy is converted to mechanical energy in a fan, light energy in a bulb, and sound energy in a computer. - Driving a car:
a. We use fuel in the form of petrol or diesel or gas to run vehicles.
b. When this fuel burns in the engine, chemical energy is converted into heat energy.
c. Burning fuel produces hot gases which pushes the piston in the engine to move the vehicle.
d. Thus heat energy is converted into mechanical energy.
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