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Rotational Inertia of Solid Disk

  1. Oct 9, 2008 #1
    1. The problem statement, all variables and given/known data

    What is the rotational inertia of a solid iron disk of mass 46 kg, with a thickness of 6.31 cm and radius of 19.4 cm, about an axis through its center and perpendicular to it?

    2. Relevant equations

    either 1/2MR^(2) or I = sigma (1->N) Mi x Ri^(2)

    3. The attempt at a solution
    I don't know what to do!!!
  2. jcsd
  3. Oct 10, 2008 #2


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    Welcome to PF!

    Hi Kickbladesama! Welcome to PF! :smile:

    Hint: divide the disc into concentric slices of thickness dr, and integrate. :wink:
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