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Question
What happens to the K.E. when
(i) the mass of the body is doubled at a constant velocity and
(ii) the velocity of the body is doubled at constant mass?
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Solution
We have, K.E. = 1/2 mv2
Hence,
(i) On doubling the mass, at a constant velocity, the K.E. becomes double its original value.
(ii) On doubling the velocity, at constant mass, the K.E. becomes (2)2 i.e., 4 times its original value.
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