Question

Give an example where the distance is not zero but the displacement is zero.

Answer 1

1. Distance: It is the actual path covered by an object in a unit interval of time.
2. Displacement: It is the shortest path covered by an object.
3. Example: Consider a body moving in a circular path of radius 7 m. Suppose the body starts at A and moves to B (a point diametrically opposite).
4. The actual distance is equal to half of the circumference, $\mathrm{\pi }\times 7\mathrm{m}=7\mathrm{\pi m}$.
5. On completion of one round, the body comes back to A where the actual distance covered by it is equal to the circumference $2\mathrm{\pi }\times 7\mathrm{m}=14\mathrm{\pi m}$ and the displacement is zero since initial and final positions are the same.

Thus, it has covered some distance so it is not zero while the displacement of the body is zero.