Question

Two cars collide head on. Initially, car A (m= 1700.0 kg) is traveling at 10.00 m/s north and car B is traveling at 25.00 m/s south. After the collision, car A reverses its direction and travels at 5.00 m/s while car B continues in its initial direction at a speed of 3.75 m/s. What was the mass of car B?

Answer 1

call north +
initial momentum
= 1700 * 10 - m * 25
final momentum
= -1700 * 5 - m *3.75
so
17,000 - 25 m = - 8,500 - 3.75 m
25,500 = 21.25 m