A ball falls to the ground as show2n below:

A potential energy = 80 J


Kinetic energy = 0


B Kinetic energy = 48 J


C = potential energy = 0


(a) What is the kinetic energy of ball when it hits the ground?


(b) What is the potential energy of ball at B?


(c) Which law you have made use of in answering this question?

a) The kinetic energy of ball when it hits the ground will be equal to the potential energy of the ball when it was about to be made to fall. Hence, the kinetic energy will be 80J.

b) The potential energy of ball at position B will be,


PE= 80 - 48


= 32J


c) With the help of law of conservation of energy which states that energy can neither be created not be destroyed but can only be changed from one form to another, the above answers can be found. Since, the total energy will remain constant in all the three given stages.


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