In each of the following, a force, F is acting on an object of mass, m. The direction of displacement is from west to east shown by the longer arrow. Observe the diagrams carefully and state whether the work done by the force is gegative, positive or zero.

Explanation

(i) in (a) the direction of force, F and displacment are perpendicular to each other. There is no displacement in the direction of force and as such work done is zero.
(ii) (b) the direction of force F and displacement are in the some direction and as such work done by the force is positive.
(iii) (c ), the force, F acts in a direction opposite to the displacement and as such work done is negative.