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Spinning Disks

  1. Nov 26, 2005 #1
    Another one that I cant figure out.

    A solid disk of mass 5.0 kg and a radius of 15.0 cm is rotating with a constant angular velocity of 10.0 rad/sec. Another disk, with the same radius but a mass of 8.0 kg, is slowly dropped upon the first disk until they rotate together. Determine the angular velocity of the system after the two disks are attached.
  2. jcsd
  3. Nov 26, 2005 #2
    Conservation of angular momentum!
  4. Nov 26, 2005 #3
    It would be approximtely 3.8 rad/s
  5. Nov 26, 2005 #4
    Would I start with

    1/2 MR(Sqared)=1/2 MR(Squared)

    That would set the two disks equal to each other. Would this be correct?
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