Car 1 has a mass of m1 = 65 103 kg and moves at a velocity of v01 = +0.78 m/s. Car 2, with a mass of m2 = 92 103 kg and a velocity of v02 = +1.4 m/s, overtakes car 1 and couples to it. Neglect the effects of friction in your answer.

Question

(a) Determine the velocity of their center of mass before the collision
m/s

(b) Determine the velocity of their center of mass after the collision
m/s
(c) Should your answer in part (b) be less than, greater than, or equal to the common velocity vf of the two coupled cars after the collision?

Answer 1

c) they should be the same, momentum is conserved.
a) M1V1+M2V2=(M1+M2)Vcmass

this answers b) also.