Flux linked with lower face of a cube

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The discussion focuses on calculating the electric flux through the lower surface of a cube containing a point charge q. Participants suggest using Gauss's Law, noting that the charge can be considered as q/6 for each face of the cube if the charge is centered. There is confusion regarding the application of the correct formula, with one participant incorrectly referencing a different equation. Clarification is sought on the exact placement of the charge within the cube, as this affects the calculation. The consensus is that the approach should yield the correct result if Gauss's Law is applied properly.
premraj59
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Homework Statement


A point charge q is placed inside a cube of side 2a. What will be the flux associated with the lower surface ABCD?

Homework Equations


I think I can apply Gauss Law here, but can't think of something connecting it with the lower surface.
∫B.dl = 1/ε° X Charge Enclosed

The Attempt at a Solution


I tried to solve it by taking charge as q/6 (as cube has 6 faces) but the solution doesn't seem to work out.
 
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You have not given enough information. Please reproduce the problem statement exactly as given.

Also, do not just say ”it does not seem to work”. In order to help you we must know exactly what you have done and what you obtained, not a vague description.
 
premraj59 said:
A point charge q is placed inside a cube of side 2a.
Where? At the center?

premraj59 said:
∫B.dl = 1/ε° X Charge Enclosed
That's not Gauss' law. Look it up.

premraj59 said:
I tried to solve it by taking charge as q/6 (as cube has 6 faces) but the solution doesn't seem to work out.
That should work fine, once you apply the right law. (Assuming the charge is at the center of the cube.)
 
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