Question

State the amount of work done by a body, when it moves in a circular path.

Answer 1

1. Work is the product of force and displacement.
2. The SI unit of work is $Joule\left(J\right).$
3. According to the formula of work,

$W=FsCos\theta$ ….(i)

Where, $\text{'}W\text{'}$ is the amount of work, $\text{'}F\text{'}$ is the applied force, $\text{'}s\text{'}$ is the displacement, and $\text{'}\theta \text{'}$ be the angle between force and displacement.

4. The work done by a body moving in a circular path is also zero.

5. This is because, when a body moves in a circular path, then the centripetal force acts along the radius of the circle, and it is at a right angle to the motion of the body.

6. So, $\theta =90°andCos90°=0$,

7. Then on putting the value of $Cos90°=0$ in equation (i) we get,

$\left(W\right)=0$.

Hence, the work done by a body moving in a circular path is zero.