Question

If we want to stop a moving cart filled with pebbles, we need to apply a larger force when compared to an empty cart. Why?

Answer 1

From Newton's second law of motion, the rate of change of momentum is directly proportional to the force applied and this change in momentum occurs in the direction of the force. Since the momentum of a cart filled with pebbles is more as compared to an empty cart moving with the same velocity, we need to apply a larger force in the former case.