Question

Which of the following can be zero when a particle is in motion for some time?

• A. speed
• B. displacement
• C. distance
• D. none of these

Answer 1

The correct option is B displacement

(A) For the scalar quantities, they depends only on the magnitude of the term. direction does not matter for scalar quantities.
(B) For the vector quantity, it depends upon the direction of that vector as well as magnitude.

So, vector sum can be zero after some time.

In this case only Displacement can be zero after some time.