Question on zero electric flux through a closed surface.

AI Thread Summary
In the discussion, a user explores the implications of Gauss's law regarding electric flux through a closed surface, specifically a cube with no enclosed charge and an electric field parallel to two faces. They question the assumption that the flux is zero when the electric field strength differs across the two faces, suggesting that unequal strengths would lead to a nonzero total flux. This raises concerns about the validity of Gauss's law in such scenarios. The user acknowledges the confusion and intends to move the discussion to a more appropriate section. The inquiry highlights the complexities of applying Gauss's law under varying electric field conditions.
student14
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I'm relearning basic electricity concepts and I can't find an answer to a situation I've thought up.

Imagine a cube with no enclosed charge and an electric field through it parallel to two of its faces. Guass's law says that the flux should be zero because there is no enclosed charge.

Every example of this that I have seen goes something like this: The four perpendicular faces have zero flux due to the sides being perpendicular to the field, and the flux from the other two sides cancel each other out. I.e if E is the strength of the electric field, A is the area of the sides of the cube, and \Phi is the total flux, then

\Phi = EA + (-EA) = 0.

But what if the strength of the electric field is not the same at both sides? Then there won't be any cancelling out and there will be nonzero flux, which is contrary to Guass's law?
 
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Sorry, I see that this thread should have been posted in the coursework section. I shall post this there and this thread can be deleted.
 
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