Question

Cart "A" is moving with a velocity of 21m/s. Cart "B" is stationary and Cart "A" collides with Cart "B". Cart "A" velocity slows to 7m/s. What is Cart "B" velocity?

Answer 1

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Answer 2

Answer:

During any type of collision, for external force 0,

Momentum of the system is always conserved.

initial velocity of car A=u1= 21 m/s, and of car B =u2=0 m/s

final velocity of car A=v1=7 m/s, and of car B= v m/s( say)

According to conservation of linear momentum,

mu1+mu2=mv1+mv( assuming identical masses)

=> u1+u2=v1+v

=> 21=7+v

=> v=14 m/s

Thus, cart B moves with 14 m/s