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Homework Help: Center of Mass of a Hollow 2D Triangle

  1. Apr 3, 2009 #1
    1. The problem statement, all variables and given/known data

    What is the center of mass a hollow 2D right triangle having legs of length A and B. The sides of the triangle are also extremely thin. Assume uniform density.

    2. Relevant equations


    3. The attempt at a solution

    [tex]\overline{x}=\int\frac{ax^2dx}{b}/\int\frac{axdx}{b}[/tex]<-something like that
    my final answer was ([tex]\frac{a^2}{b}[/tex],[tex]\frac{b^2}{a}[/tex])

    Attached Files:

  2. jcsd
  3. Apr 3, 2009 #2


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    Welcome to PF!

    Hi datdo! Welcome to PF! :smile:

    (i can't see your picture yet, but …)

    Wouldn't it be simpler to replace each side by an equal mass at its centre? :wink:
  4. Apr 4, 2009 #3
    hmm.... i didn't think of that...

    Oh but I had to use integrals. I should have put in the problem.
    Last edited: Apr 4, 2009
  5. Apr 4, 2009 #4


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    Hi datdo! :smile:
    yeeees :rolleyes:

    ok, then for the x-coordinate divide the triangle into "vertical" slices of thickness dx …

    then for the bottom side just integrate xdx, and for the slanty side integrate … ? :smile:
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