A body of mass m is moving in a circle of radius r with a constant speed v. The force on the body is $\frac{{\mathrm{mv}}^2}{\mathrm{r}}$ 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

  $\frac{{\mathrm{mv}}^2}{{\mathrm{\pi r}}^2}$

• B

  Zero

• C

  $\frac{{\mathrm{mv}}^2}{{\mathrm{r}}^2}$

• D

  $\frac{{\mathrm{\pi r}}^2}{{\mathrm{mv}}^2}$