Stuck on this problem:

A train car (mass 15,000 kg) moving right with a velocity of 4.0 m/s collides with a train car (mass 14,000 kg) moving right with a velocity of 0.5m/s. They couple or get stuck together. What is the final velocity

1 answer

momentum is conserved

(m1 * v1) + (m2 * v2) = (m1 + m2) * v3