Question

Imagine a 0.2 kg ball moving at 5 m/s colliding with a 0.3 kg ball moving at 2 m/s in the same direction. After the collision the 0.2 kg green ball stops moving and the 0.3 kg purple ball continues moving in the same direction.

Answer 1

`m1v1 + m2v2 = m1v3 + m2v4`

`(0.2 x 5) + (0.3 x 2) = (0.2 x 0) + (0.3 x v4)`

`1.0 + 0.6 = 0 + 0.3v4,  0.3v4 = 1.6`

`v4 = 1.6/0.3 = 5.3 m/s (2 sf)`