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Flux through distorted surface

  1. Dec 22, 2015 #1
    There is a distorted surface and the source of the flux is inside the cube

    View attachment 93566

    I have read that flux through it would be q/2ε0 I want to know Why?It is not my homework problem and I think it does not involve any calculation that's why I did not post it in homework section .There should be some basic reasoning behind it as in a cube flux through one of it's face is q/6ε0 because any of it's face would have 1/6th area .But what's going on here?

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    Last edited: Dec 22, 2015
  2. jcsd
  3. Dec 22, 2015 #2
    So, the source of the flux was inside the cube.

    If the source of the flux is within and in the plane of the circle then half the flux will go up into the surface and half will escape downward.
  4. Dec 22, 2015 #3
  5. Dec 22, 2015 #4
  6. Dec 22, 2015 #5
    But why equal distribution of flux takes place?
  7. Dec 22, 2015 #6
    I the distribution from the source is not equal, then we have to know what it is in order to solve the problem. I also assume the problem is solvable. Since we are not told what the distribution of the source is, I deduce it is equal, because otherwise the problem is not solvable.. These are just the sorts of conventions one has to deal with when solving toy problems of this type.
  8. Dec 22, 2015 #7


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    Since the medium in which the charge is placed is homogenous (i.e. with same permittivity everywhere), flux will be uniformly distrobuted in all the directions.
  9. Dec 22, 2015 #8
    You mean medium surrounding the distorted surface is vacuum?But nothing such is mentioned.
  10. Dec 22, 2015 #9


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    There's εo in your answer in #1. If the medium weren't homogenous, there would be something more given in the problem statement, as Hornbein said in #6.
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