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Homework Help: Physics Hwk. problem: Conservation of Linear Momentum

  1. Oct 18, 2004 #1
    55 kg swimmer is standing on a stationary 225 kg floating raft. The swimmer then runs off the raft horizontally with a velocity of +4.4 m/s relative to the shore. Find the recoil velocity that the raft would have if there were no friction and resistance due to the water.

    I used the equation vf2=-m1*vf1 divided by m2, but the answer is wrong. Did I use the wrong equation? Please Help!!!
  2. jcsd
  3. Oct 18, 2004 #2
    Hey I had this same homework problem. Almost exactly infact. The only thing different is your raft weighs 225kg and mine weighed 230kg. And I got the problem correct so I think I can help you.

    The equation you are using is correct. What was your answer?
  4. Oct 19, 2004 #3
    Physics Hwk. Problem: Conservation of Linear Momentum

    Thanks, the answer i got is -1.08.
  5. Oct 19, 2004 #4
    That should be the correct answer then. Unless your using webassign and it requires 3 significant digits. Then you are rounding too soon.
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