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Homework Help: Momentum and Angles

  1. Nov 16, 2009 #1
    1. The problem statement, all variables and given/known data

    A golf ball of mass 0.045 kg is moving in the +x-direction with a speed of 6.10 m/s, and a baseball of mass 0.145 kg is moving in the -y-direction with a speed of 2.20 m/s. What are the magnitude and direction of the total momentum of the system consisting of the two balls?


    _________° (from the +x axis)

    2. Relevant equations

    P=mv and I'm not sure what else...

    3. The attempt at a solution

    My teacher said that we should be able to teach ourselves momentum, so as one might be able to tell, I'm not sure where to start.
    I tried doing (.045x6.1) + (.145x2.2) = P, but that didn't work. How should I start? Are there other equations I should know?

    Thank you so much for your help!
    Last edited: Nov 16, 2009
  2. jcsd
  3. Nov 16, 2009 #2
    Did you learn about center of mass? I'm sure your textbook probably has a section on it. The momentum of the system is the same as the momentum of the center of mass of the system.
  4. Nov 17, 2009 #3


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    Momentum is a vector, with the same direction as the velocity of the object. You need to add the two momenta as vectors; don't simply add (.045x6.1)+(.145x2.2).
  5. Nov 18, 2009 #4
    I just solved it, thank you everyone!

    (I did pythagorean theorum and for the angle I just did tangent!)
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