Q16 of 33 Page 158

An object of mass ‘m’ is moving with a constant velocity ‘v’. How much work should be done on the object in order to bring the object to rest?

Initial kinetic energy of the object, K.E. (Initial) = mv2

When the object comes to rest, final kinetic energy of the object, K.E. (Final) = 0


Change in kinetic energy = mv2 - 0


= mv2


Work done on the object = Change in its kinetic energy


= mv2


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