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Moment of Inertia of a Sphere derivation?

  1. May 10, 2015 #1
    Hi,

    Is there a way to derive the moment of inertia of a sphere without using the M of I of a cylinder? In other words, is it possible to find a sphere's from scratch? Please include a derivation in your answer, unless there isn't one of course.
     
  2. jcsd
  3. May 10, 2015 #2

    Orodruin

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    Why don't you just integrate over the sphere to get it?
     
  4. May 10, 2015 #3
    can you explain to me how to do that?
     
  5. May 10, 2015 #4

    Orodruin

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    Do you know the expression for the moment of inertia for an arbitrary object?
     
  6. May 10, 2015 #5
    I do, but I don't know how to properly set the equation so that I can integrate.
     
  7. May 10, 2015 #6

    PeroK

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  8. May 10, 2015 #7

    SteamKing

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    Of course there is a way to derive the MOI of a sphere or any other body from scratch. Do you think we make these things up to torture college freshmen?

    This article:

    http://www.solitaryroad.com/c375.html

    contains the general method for calculating mass, the location of centroids, and the mass moment of inertia for a general body.

    See Section II - Moments of inertia of masses.
     
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