Question

A railroad car moving at a speed of 3.41 m/s overtakes, collides, and couples with two coupled railroad cars moving in the same direction at 1.40 m/s. All cars have a mass of mass 1.07 x 10^5 kg. Determine the following. (a) speed of the three coupled cars after the collision (Give your answer to at least two decimal places.) (b) kinetic energy lost in the collision

Answer 1

2.07 m/s

Step-by-step explanation:

m = 1.07 x 10^5 kg, u1 = 3.41 m/s, u2 = 1.4 m/s

Let the speed of three coupled car after collision is v

Use conservation of momentum

m x u1 + 2 m x u2 = 3 m x v

u1 + 2 u2 = 3 v

3.41 + 2 x 1.4 = 3 v

v = 2.07 m/s