p = mv

Scenario #4
At a station ,a train weighs approximately 1000kg and is moving at 50m/s on a railway and collides with an incoming train weighing 1000kg and moving at -20m/s.

1)If these two trains stick together and begin to move after having being collided with one another , at what velocity will they move at?

2)The collision that occurred was an inelastic one , Suppose if the collision that occurred was a elastic one , at what rate of speed will the trains move at on the railway?

3)If the trains weighed 2000kg what will be the momentum of the trains?

1 answer

1. M1*V1 + M2*V2 = M1*V + M2*V.
1000*50 - 1000*20 = 1000V + 1000V,
30,000 = 2000V,
V = 15 m/s.

3. Momentum = 2000*50 - 2000*20 = 60,000 kg*m/s.