A 7.0-kg bowling ball strikes a 2.0-kg pin.The pin flies forward with a velocity of 6.0 m/s;the ball continues forward at 5.0 m/s.What was the original velocity of the ball?
A) 4.0 m/s
B) 5.7 m/s
C) 6.7 m/s
D) 3.3 m/s

Question

Quizplus · Accepted Answer

Using the law of conservation of momentum: 
p(initial) = p(final) 
where p = mass x velocity 
(7.0 kg)(v) = (7.0 kg)(5.0 m/s) + (2.0 kg)(6.0 m/s) 
7v = 35 + 12 
v = 6.7 m/s 
Therefore, the original velocity of the ball was 6.7 m/s.

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