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Velocity and Momentum

  1. Dec 15, 2009 #1
    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
  2. jcsd
  3. Dec 15, 2009 #2
  4. Dec 15, 2009 #3
    No i didn't find inertia, but the whole worksheet is dealing with momentum and impulse.
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