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Homework Help: Moment of inertia for an irregular shaped object

  1. Nov 6, 2005 #1
    An irregular shaped object of mass 2.45 kg has a moment of inertia 5.782 kgm2 about an axis through a point 1.40 m from its center of mass. Calculate the moment of inertia about a parallel axis through its center of mass.

    I used the parallel axis theorem,
    I= I_c + Mh^2
    I= 5.782 +(2.45)(1.40)^2
    I= 10.6 kgm^2

    This wasn't right.. can someone tell me what I'm doing wrong. Thanks
     
  2. jcsd
  3. Nov 6, 2005 #2

    Pyrrhus

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    You are asked for the moment of inertia about the centroid, yet you are calculating the moment of inertia about a parallel axis to the centroid axis...
     
  4. Nov 6, 2005 #3
    I_c is not 5.782, I_C is what your solving for.

    I just got beaten to it. Have fun cyclovenom, im going back to learning matlab.
     
  5. Nov 6, 2005 #4
    ok I got it.. thanks
     
  6. Nov 6, 2005 #5

    Pyrrhus

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