A railway boxcar is moving toward a stationary boxcar on a rail with negligible friction. The stationary boxcar is twice the mass of the moving one. On collision, the boxcars couple to each other. After the collision, what is the velocity of the more massive boxcar? Express your answer as a fraction of the velocity of the less massive boxcar before the collision.
A)1/2
B)1/3
C)-1/3
D)-1/2

Question

Quizplus · Accepted Answer

Using conservation of momentum, the final velocity of the coupled boxcars is one-third of the initial velocity of the moving boxcar.

A Railway Boxcar Is Moving Toward a Stationary Boxcar on a Rail