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Homework Help: Charge over a triangular region

  1. Jan 21, 2010 #1
    1. The problem statement, all variables and given/known data
    -Given that [tex]\rho_{v}[/tex]=6xy C/[tex]m^{2}[/tex], Calculate the total charge on the triangular region.

    -the verticies of the triangle are: (0,0), (2,2) and (4,0)


    2. Relevant equations

    [tex]Q=\int_{s}\rho_{v}ds[/tex]

    3. The attempt at a solution

    [tex]=\int^{4}_{0}\int^{-x+4}_{x}6xy dydx[/tex]
    [tex]=\int^{4}_{0}48x - 24x^{2} dx[/tex]
    [tex]=24x^{2}-8x^{3}|^{4}_{0}[/tex]
    [tex]=-128C[/tex]

    According to the textbook the correct answer is 32C

    any help would be appreciated!
    Thanks,
     
  2. jcsd
  3. Jan 21, 2010 #2

    kuruman

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    Science Advisor
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    Gold Member

    You got your integration limits mixed up. The maximum value for x is 2 m. Draw a picture and you will see why.
     
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