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Angular speeds and a basketball

  1. Apr 22, 2004 #1
    I don't know how to solve the following problem:

    A basketball rolls along the floor with a constant linear speed V. (a) Find the fraction of its total kinetic energy that is in form of rotational kinetic energy about the center of ball.

    I think the answer is 2/5. But i don't know how to do it.
  2. jcsd
  3. Apr 22, 2004 #2

    Doc Al

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    Staff: Mentor

    The total KE is the sum of the translational and rotational KE (about center of mass).
    The translational KE = 1/2 MV2
    The rotational KE = 1/2 Iω2, where I is the rotational inertia of a spherical shell about its center (look it up!)

    One can assume that it is rolling without slipping, which means that V = ωR.
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