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Homework Help: Exploding ball

  1. Oct 17, 2006 #1
    A ball, initially at rest at the coordinate origin, explodes into three equal pieces. After explosion, one piece moves along x-axis with velocity VX1 = 4.00 m/s and another piece move with velocity: VX2 = 3.83 m/s and VY2 = 9.07 m/s. What are the velocity components for the third piece?

    This confuses me because I am unsure of what direction the third piece would travel after the explosion. It could go into second quadrant and have an negative x component; it could go into the third quadrant and have both negative x and y components.

    How do I begin this problem?
     
  2. jcsd
  3. Oct 17, 2006 #2

    berkeman

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    Staff: Mentor

    Hint 1 -- they said "three equal pieces", by which you can assume equal mass.

    Hint 2 -- Use conservation of linear momentum in 3 dimensions. What was the net linear momentum in each of the 3 coordinates before the explosion?
     
  4. Oct 17, 2006 #3
    p=mv
    since v=0, then initial momentum of the three coordinates = 0.

    Knowing this, what step should I take next? I can't seem to think outside the box on this one...
     
  5. Oct 17, 2006 #4

    berkeman

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    Staff: Mentor

    Good, and since p and v are vectors in 3-space, you can write the 3 sums for the 3 coordinate axes and set them equal to zero, right? That should give you the answers you need.
     
  6. Oct 17, 2006 #5
    thanks a lot@!
     
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