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Homework Help: Angular Collisions

  1. Nov 26, 2006 #1
    This is an angular inelastic collision problem:

    Mary, Bob and Jane are having a snowball fight. Mary throws a 50g snowball 60 degrees S of E at 6 m/s. Bob throws his 15g snowball 2.75m/s north. Jane's throws her 35g snowball at 3.25m/s west. How fast and what is the direction of the huge snowball?

    So do I resolve each velocity vector and then sub in the formula v=(m1v1+m2v2+m3v3)/(m1+m2+m3)
     
  2. jcsd
  3. Nov 26, 2006 #2

    radou

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    Yes, since angular momentum is conserved. Note only that v, v1, v2 and v3 are vector quantities.
     
  4. Nov 26, 2006 #3
    Now I'm confused. Is each vector multiplied by the mass then added together?
     
  5. Nov 26, 2006 #4

    radou

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    Yes, it is.
     
  6. Nov 26, 2006 #5
    I'm getting 2.34m/s due south
     
  7. Nov 26, 2006 #6

    radou

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    Which doesn't seem correct, unless I'm missing something. Go through your calculations again.
     
  8. Nov 26, 2006 #7
    Should I be using -60 degrees or 60 degrees?
     
  9. Nov 26, 2006 #8

    radou

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    Use 60 degrees, but watch out for the sign of the unit vectors i and j.
     
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