Q. 165.0( 2 Votes )
Illustrate the law of conservation of energy by discussing the free fall of a body.
Answer :
According to law of conservation of energy, energy can neither be created nor be destroyed. It can only be transformed from one form to another. whenever energy changes from one form to another, the total amount of energy remains constant.
Law of conservation of energy is valid in all situations and for all kinds of energy transformations.
For example: When a body is at some height from earth it possess only potential energy, as the body falls downwards then its potential energy goes on decreasing but kinetic energy goes on increasing.
Just before hitting the ground entire potential energy is transformed into kinetic energy and it posesses only kinetic energy.
Total energy= kinetic + potential energy
At maximum height, kinetic energy = 0
Total energy = potential energy
On hitting ground, potential energy = 0
Total energy = kinetic energy
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