Answer:
When displacement caused by force is zero or force is perpendicular to displacement then we consider there will be no work done
Explanation:
We know that work done is given by [tex]W=Fdcos\Theta[/tex], here F is force applied and d is the displacement caused by the force
Now there are two case in which work done will be zero that is, either displacement is zero or [tex]\Theta =90^{\circ}[/tex] that is force and displacement are perpendicular to each other
So when displacement caused by force is zero or force is perpendicular to displacement then we consider there will be no work done
