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Homework Help: Moment of inertia

  1. Apr 17, 2005 #1
    First of all i have a final exam tomorrow on Classical Mechanics - Cna someone point out a place that has the derivations of the moments of inertia for various objects

    Now if there a disc of mass M spinning about an axis taht is perpendicular to the plane of the disc, and the plane of the disc is horizontal (parallel to earth's surface) then it's moemnt of inertia is [itex] \frac{1}{2} MR^2 [/itex]

    if there was a little mass located at a point that is r, where r<R from the center of the disc then the moment of inertia is [itex] I = \frac{1}{2} MR^2 + mr^2 [/itex]
    is this correct??

    Also , in class my prof said that on the exam he would have a question in which we would have to calculate a work integral... what is that ??
    as far as im concerned [itex] W = \int F \cdot d [/itex] is there anything more to it?? Can you point out an example of something that is more complicated liek that??
    Last edited: Apr 17, 2005
  2. jcsd
  3. Apr 17, 2005 #2


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    So the little mass is standing on the disk?It's okay,then...

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