Question

Two bodies are accelerating towards each other. After sometime they collide. Which one of the following statements is true about the system?

(a) The total momentum remains conserved about the instant of collision

(b) The total momentum remains conserved during collision

(c) The total momentum does not remain conserved

(d) The total momentum remains conserved

This question was addressed to me by my school principal while I was bunking the class.

My doubt is from Laws of Motion topic in chapter Laws of Motion of Physics – Class 11

Answer 1

Right answer is (a) The total momentum remains conserved about the instant of collision

For explanation I would say: The two bodies are accelerating and they collide. Since they are accelerating the total momentum does not remain conserved during the motion. But at the instant of collision, both the bodies have a constant velocity. Hence, just before and just after the collision, the total momentum will remain conserved.