Work is done on a body only when-
A. It experiences energy gain through a mechanical effect
B. Forces work on it
C. There is displacement
D. It moves through a certain distance
Answer: Option C
Solution (By Examveda Team)
Work is defined in physics as the product of force and displacement in the direction of the force.This means that work is only said to be done when a force causes displacement of a body.
If there is no displacement, even if a force is applied, no work is done in the physics sense.
Option A is incorrect because energy gain alone doesn't confirm that mechanical work has occurred—it must involve displacement.
Option B is misleading; forces may act on a body, but without displacement, no work is done.
Option D is close, but too vague—movement alone isn't enough; it must be displacement caused by a force.
Therefore, Option C is correct because displacement is the essential condition for work to be done on a body.
This Question Belongs to Physics GK Chapter Wise >> Work, Energy And Power
The correct answer is C. There is displacement.
Explanation:
In physics, work is done on a body only if there is displacement of the body in the direction of the applied force.
Simply applying a force is not enough — without displacement, no work is done.
The formula for work is:
W = F * d *costheta
Why the others are not the best answer:
A: Energy gain is a result, not the direct condition for work.
B: Forces may act without displacement (e.g., pushing against a wall).
D: Moving "through a certain distance" alone isn't enough; it must be linked with an applied force causing displacement in its direction.