Question

A body of mass $m$ is moving in a circle of radius $r$ with a constant speed $v$. The force on the body is $\frac{mv^{2}}{r}$ 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. $\frac{mv^{2}}{r} \times \pi r$
• B. Zero
• C. $\frac{mv^{2}}{r^{2}}$
• D. $\frac{\pi r^{2}}{mv^{2}}$

Answer 1

Answer: (B)

Zero

Answer 2

Work done by centripetal force is always zero.