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Electric flux through a cube

  1. Feb 3, 2012 #1
    A point charge 6.50 nC is at the center of a cube with sides of length 0.260 m.

    PART A: What is the electric flux through the surface of the cube?

    PART B: What is the electric flux through one of the six faces of the cube?


    Total flux enclosed by the cube = Q / eo
    6.5E-9/8.85 x 10^-12= 734.5

    flux through one of the six faces is
    = Q / 6 eo
    so 734.5/6 = 122.4

    with the exception of units, are these right? i think i'm doing it wrong because i didn't use the side length in any of the calculations.
  2. jcsd
  3. Feb 3, 2012 #2


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    hi kirvy2! :wink:
    no, your method is fine :smile:
  4. Feb 3, 2012 #3


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    Agreed. It is one of the interesting things about the Coulombic force :) Maybe they were throwing you a red herring by giving you the length of the sides.
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