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Homework Help: Resulting Angular Speed? Help!

  1. Apr 8, 2010 #1
    1. The problem statement, all variables and given/known data

    A flat uniform circular disk (radius = 2.18 m, mass = 1.22E+2 kg) is initially stationary. The disk is free to rotate in the horizontal plane about a frictionless axis perpendicular to the center of the disk. A 42.9 kg person, standing 1.29 m from the axis, begins to run on the disk in a circular path and has a tangential speed of 2.20 m/s relative to the ground. Calculate the resulting angular speed of the disk (in rad/s).

    I don't even know where to start. Please help?!
  2. jcsd
  3. Apr 8, 2010 #2


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    Staff Emeritus
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    One hint: angular momentum.
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