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Moment Of Inertia Of Sphere At A Distance

  1. Nov 17, 2008 #1
    If a sphere is at a certain radius from the axis of rotation greater then the radius of the sphere can you just take the moment of inertia as a point mass, I=mr^2?

    Thanks for your time.
  2. jcsd
  3. Nov 17, 2008 #2

    Doc Al

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    Staff: Mentor

    No. Use the parallel axis theorem to find the moment of inertia about the axis.
  4. Nov 17, 2008 #3
    We have two radii to define: one for the shape of the sphere and the other for the (circular) movement it is in.
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