what is the size and direction of the final velocity of the two cars when a 0.4 kg toy train car moving forward at 3 m/s collides with and sticks to a 0.8 kg toy car that is traveling the opposite direction of -2 m/s

Answer 1

original momentum in x direction
= .4*3 - .8*2
= 1.2 -1.6
= -0.4 kg m/s
so moves to left if first car was moving right

final momentum in x direction = (1.2)v
final momentum = original momentum (first law)
1.2 v = -0.4
v = - 1/3 meter/second

Answer 2

Thank I needed help thank you.