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Homework Help: Electric flux through a multihedral face

  1. Feb 1, 2009 #1
    1. The problem statement, all variables and given/known data
    An object with a charge of 0.920 C is placed at the center of a regular tetrahedron with 4 equivalent surfaces. What is the electric flux through one surface of the tetrahedron?


    2. Relevant equations
    For an n-sided polygon

    Electric Flux = Charge / (n)(Eo)


    3. The attempt at a solution

    No idea, I am lost on this one...
     
  2. jcsd
  3. Feb 1, 2009 #2

    Delphi51

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    Homework Helper

    Think of the tetrahedron surface enclosing the charge. You can easily calculate the total flux through the whole surface using your formula.

    Now, what fraction of that will go through one face of the tetrahedron? Note: be sure you know what a "regular" tetrahedron is.
     
  4. Feb 1, 2009 #3
    I'm just lost on what Eo is?
     
  5. Feb 1, 2009 #4

    Delphi51

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    Homework Helper

    Eo in Gauss' law is supposed to be written epsilon sub zero, the permittivity of free space.
    It is 8.85 x 10^-12 farad/meter.
    Check it out at http://en.wikipedia.org/wiki/Electric_constant
    They have other names for it and several variations on the units that could be useful to you here.
     
  6. Feb 1, 2009 #5
    Hey thanks man, my professor failed to tell us that and its not in this useless pc text book. I appreciate it!
     
  7. Feb 1, 2009 #6
    so should it be 0.92C/4(8.85x10^-12) = 2.59887e10?
     
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