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Moment of Inertia, relation to other moments?

  1. Dec 29, 2009 #1


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    Gold Member

    Is there a reason the moment of inertia is called the "moment" of inertia? A while back, for whatever reason, I remembered how the moment of inertia is formulated and I realized it had similarities to the e/m moments; that is the integration of the mass density multiplied by coordinates. In particular, it looked like the quadrapole moment. Is there any connection? Was it simply a convenient name to give to e/m moments?
  2. jcsd
  3. Dec 29, 2009 #2


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    Mechanical moments (from a mathematical point of view) are average values of density times distance (raised to some power) from the center of mass of the object. The moment of inertia is the second moment.

    e/m moments have a similar mathematical structure, but e/m quantities replace material density.
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