Q14 of 42 Page 31

Two billiard balls A and B, each of mass 50g and moving in opposite directions with speed of 5m s-1 each, collide and rebound with the same speed. If the collision lasts for 10-3 s, which of the following statements are true?

Given that speed of each ball v=5 m/s and mass of each ball m=0.005 kg.

So initial momentum of each ball





⇒


The direction of the velocity of each ball is reversed after the collision so final momentum of each ball





⇒


So from above result it is obvious that option (d) is correct.


As we know change in momentum of each ball is equal to impulse imparted to each ball



⇒


⇒


⇒


So from here we can say options (a) and (b) are wrong and option (d) is correct.

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