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Homework Help: Angular momentum problem?

  1. Jun 21, 2012 #1
    1. The problem statement, all variables and given/known data

    Near the South Pole, a supply plane going at 120 mph drops a 60 kg supply package into a sled that was initially at rest. After the package lands in the sled, the speed of the sled was found to be 30 m/s. Estimate the mass of the sled.

    2. Relevant equations


    3. The attempt at a solution

    Now i know that vertical velocity and horizontal velocity are independent of each other. So it would seem like i just plug, play, and solve for the unknowns. But this seems all too easy, like maybe the vertical motion has an effect on the final velocity. Anyone help?
  2. jcsd
  3. Jun 21, 2012 #2

    Doc Al

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    Staff: Mentor

    Looks like a straightforward conservation of momentum problem. (Linear, not angular, of course.) Vertical motion won't factor in.
  4. Jun 21, 2012 #3
    You know thats what i thought, but this teacher is brutal, always throwing trick questions, so i thought i was missing something here.
  5. Jun 21, 2012 #4
    Hi jcurtis912! Welcome to Physics Forums :smile:

    Why would the vertical velocity have an effect on final horizontal velocity? The conservation of linear momentum clearly states that the momentum in one direction is conserved if there is no net force acting in that direction, and this holds for the given problem.

    Edit : Seems I'm quite late...I left the screen open before submitting :tongue2:
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