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Homework Help: Collisions on 2Dimensions.

  1. Sep 26, 2007 #1
    A 5.00 kg Ball A moving at 12.0 m/s collides with a stationary 4.00 kg Ball B. After
    the collision, Ball A moves off at an angle of 38.0º right of its original direction. Ball B 52.0º left of Ball A's original direction. After the collision, what is the momentum
    of Ball A?

    P1 + P2 = P1' + P2'
    60 + 0 = P1' + P2'

    After this I have no idea where to go. We would need a velocity however there isnt one given.

    I'm assuming a vector diagram would be useful, but Im not too sure what that would look like.
  2. jcsd
  3. Sep 26, 2007 #2


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    Homework Helper

    You must break up the momentum into the x and y components, and sum up in each direction. Draw a diagram to keep track of everything.
  4. Sep 27, 2007 #3
    I dont have the hypotenuse to be able to do that. The only thing I could think of would be x =(60-y) and y=(60-x)
  5. Sep 27, 2007 #4
    Ok so I also asked this question on Yahoo answers, and some person gave me this:

    Now I have never seen anything alike this taught to me. Does this have any truth to it?

    I was also given this which seems more.... legit

  6. Sep 27, 2007 #5
    You don't need the hypotenuse to break into components. You have the angle given after the impact, use trigonometry.


    The first response is completely off. The second one seems right to me as well.
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