Question

Work done is zero:(a) When force and displacement are in the same direction.
(b) When force and displacement of the body are in opposite directions(c) When force acting on the body is perpendicular to the direction of the
displacement of the body.
(d) When force makes an angle with displacement

Answer 1

Answer:

Option (c) When force acting on the body is perpendicular to the direction of the  displacement of the body.

Explanation:

Since Work is the dot product in between the force and displacement.

$w.d = f.d$

$w.d = fdcos(\theta)$

where $\theta$ is the angle between force and displacement.

So, for getting the work done zero both force and displacement must be perpendicular to each other because $cos(\thet90) = 0$

So, option (c) When force acting on the body is perpendicular to the direction of the  displacement of the body.