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Question
Two billiard balls, each of mass 0.05 kg, moving in opposite directions with speed 6 ms-1collide and rebound with the same speed. What is the impulse imparted to each ball due to the other?
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Solution
Initial momentum of each ball before collision
= 0.05 x 6 kg ms-1 = 0.3 kg ms-1
Final momentum of each ball after collision
= -0.05 x 6 kg ms-1 = -0.3 kg ms-1 Impulse imparted to each ball due to the other
= final momentum - initial momentum = -0.3 kg m s-1 - 0.3 kg ms-1
= -0.6 kg ms-1 = 0.6 kg ms-1 (in magnitude)
The two impulses are opposite in direction.
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