Question

Give one example when work done by a body is negative

Answer 1

in this attachment we can see that the man is providing force in upward direction but the ball is displacing in downward direction

Workdone by man in this case is negative

because the angle between the force applied by man and the displacement of the body is 180 degree

W = Fdcos180

W= - Fd

here F is force applied by man on ball

and d is displacement of ball