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Question
When a body moves in a circular path, how much work is done by the body? Give reason.
(Hint: The body is acted upon by the centripetal force.)
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Solution
When a body moves in a circular path, no work is done since the force on the body is directed towards the centre of circular path (the body is acted upon by the centripetal force), while the displacement at all instants is along the tangent to the circular path, i.e., normal to the direction of force.
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