A body of mass m is moving in a circle of radius r with a constant speed v . force on body is frac{{

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5.Work, Energy, Power and Collision

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A body of mass $m$ is moving in a circle of radius $r$ with a constant speed $v$. The force on the body is $\frac{{m{v^2}}}{r}$ and is directed towards the centre. What is the work done by this force in moving the body over half the circumference of the circle

A

$\frac{{m{v^2}}}{r} \times \pi r$

B

Zero

C

$\frac{{m{v^2}}}{{{r^2}}}$

D

$\frac{{\pi {r^2}}}{{m{v^2}}}$

Solution

(b)Work done by centripetal force is always zero.

Standard 11

Physics

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