Question on zero electric flux through a closed surface.

In summary, the conversation discusses a cube with no enclosed charge and an electric field through it parallel to two of its faces. According to Gauss's law, the flux should be zero in this situation. However, when considering the strength of the electric field on each side, there may be nonzero flux, which contradicts Gauss's law. The speaker realizes this should have been discussed in the coursework section and apologizes for posting in the wrong place.
  • #1
student14
4
0
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 [itex] E [/itex] is the strength of the electric field, [itex] A [/itex] is the area of the sides of the cube, and [itex] \Phi [/itex] is the total flux, then

[itex] \Phi = EA + (-EA) = 0 [/itex].

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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  • #2
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.
 

Related to Question on zero electric flux through a closed surface.

1. What is electric flux?

Electric flux is the measure of the amount of electric field passing through a given area. It is a vector quantity and is represented by the symbol Φ.

2. What is a closed surface?

A closed surface is a three-dimensional shape or boundary that encloses a volume. It has no openings and can be any shape, such as a sphere, cube, or cylinder.

3. Why is the electric flux through a closed surface important?

The electric flux through a closed surface is important because it allows us to calculate the net electric charge enclosed within the surface. It is also useful in understanding the behavior of electric fields and their interactions with different materials.

4. Is it possible to have zero electric flux through a closed surface?

Yes, it is possible to have zero electric flux through a closed surface. This can happen when the electric field is parallel to the surface, so there is no component of the field passing through the surface.

5. How can the electric flux through a closed surface be calculated?

The electric flux through a closed surface can be calculated using Gauss's Law, which states that the electric flux through a closed surface is equal to the enclosed electric charge divided by the permittivity of the material. Mathematically, it can be represented as Φ = Q/ε, where Q is the enclosed charge and ε is the permittivity of the material.

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