(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

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?

2. Relevant equations

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

3. 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

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# Velocity and Momentum

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