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Dbl. int. - center of mass

  1. Mar 1, 2005 #1
    Any hints on how to approach this problem?

    A lamina occupies the part of the disk [itex]x^2 + y^2 <= 1[/itex] in the first quadrant. Find the center of mass if the density at any point is proportional to the square of its distance from the origin
    Last edited: Mar 1, 2005
  2. jcsd
  3. Mar 1, 2005 #2
    And just for future reference, how do you do inequalities in latex?
  4. Mar 1, 2005 #3
    [tex] \leq {and} \geq [/tex] the code reference file is found by clicking on the code and then clicking the link
  5. Mar 1, 2005 #4
    I don't know what responses you got for your earlier thread. I could not find it. Any way, use the following to find the CM.

    [tex] M r_{cm} = \int r_m dm[/tex]

    Since the density depends only on the radius, CM should be along the [itex]\theta = \pi/2 [/itex] line.

    Choose a small element at [itex](r, \theta )[/itex] and proceed.
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