Question

A particle describe a horizontal circle of radius 0.5m with uniform speed. the centripetal force acting is 10 N. the work done in eescribing a semicircle is:

Answer 1

if centripetal force acting then angle between force and radius is 90°
and work done = FSCosθ
                         = 10 x 0.5 x Cos90°
                         = 5 x 0 = 0 joule
work done is zero joule.

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