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Question
A heavy car A of mass 2000 kg travelling at 10 m/s has a head-on collision with a sports car B of mass 500 kg. If both cars stop dead on colliding, what was the velocity of car B ?
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Solution
m1 × v1 = m2 × v2
m1 = 2000 kg,
v1 = 10 m/s
m2 = 500 kg
v2 = ?
2000 × 10 = 500 × v2
20000 = 500 × v2
v2 = 20000/500
= 40 m/s
The velocity of car B is 40 m/s.
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