Certain force acting on a 20 Kg mass changes its velocity from 5 m/s to 2 m/s. Calculate the work done by the force ? -Physics 9th

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Answer :

Certain force acting on 20 kg mass changes its velocity from 5 m s-1 to 2 m s-1. Calculate the work done by the force. (E k)2 = (1 )/2x 20 — (2)2 = 40 J.

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