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Homework Help: Don't know how to start

  1. Nov 30, 2004 #1
    Here is my question I'm not sure even how to come up with the answer:

    A circular pizza of radius R has a circular piece of radious R/2 removed from one side. The center of gravity has moved from C to C' along the x axos. Show that the distance from C to C' is R/6. Assume the thickness and density of the pizza are uniform throughout.

    If anyone could give me some pointers they would be greatly appreciated.
  2. jcsd
  3. Dec 1, 2004 #2
    Find the center of mass of the pizza (in the center, obviously) and then find the center of mass of the removed piece.

    Xcom = (m1x1 + m2X2) / (total mass)

    If the pizza has density d, then the total area must be R^2*pi - (R/2)^2*pi. This goes in the denominator. Now you simply find the center of mass of the removed piece, which should be (R/2)^2*pi. Multiply this by R/2 (the distance to the center). I hope that helps some.
  4. Dec 3, 2004 #3

    Doc Al

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    Staff: Mentor

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