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