Velocity and Momentum

[jazzysoshort]

Homework Statement

In a freight yard a train is being put together from freight cars. An empty freight car, coasting at 10m/s, strikes a loaded car that is stationary, and the cars couple together. Each of the cars has a mass of 3000 kg when empty, and the loaded car contains 12,000 kg of canned soda. With what speed does the combination of the two cars start to move?

Homework Equations

p=mv (f)(change in time)=p

The Attempt at a Solution

calculated p for empty car p=(10)(3000) p=30,000
calculated the full momentum p=(10)(15000) p=150,000
totaled the masses to find the velocity 180,000=18,000v v=180 m/s

 

[Centurion1]

nvm.

 

[jazzysoshort]

No i didn't find inertia, but the whole worksheet is dealing with momentum and impulse.