Question

A particle describe a horizontal circle of radius 0.5 m with
uniform speed. The centripetal force acting is 10 N. The
work done in describing a semicircle is
(a) zero (b) 5 J
(c) 5 π J (d) 10 π J

Answer 1

Explanation:

If centripetal force acting then angle between force and radius is 90°

and work done = FSCosθ

                        = 10 x 0.5 x Cos 90°

                        = 5 x 0 = 0 joule

work done is zero joule.

opt A