Gauss Law in a plane sheet, and thick sheet (Infinite)

AI Thread Summary
The discussion focuses on the application of Gauss's Law to charged sheets, highlighting the derived equations for electric field (E) in both thick and thin sheets. The formula for a thick sheet is E=σ/ϵ, while for a thin sheet, it is E=σ/2ϵ. A participant expresses confusion about how these equations align with the inverse square law of distance, questioning if this relationship is maintained. It is clarified that while individual charge contributions follow the inverse square law, the geometry of the charged plane modifies the overall electric field behavior. The conversation emphasizes the importance of understanding how geometry influences electric field calculations in different scenarios.
Prannoy Mehta
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We have learned the below formula for a plane sheet of charge with thickness.

E=σ/ϵ

and the one below for with no thickness (negligible)

E=σ/2ϵ

The problem, I am facing is digesting the derived equations. It is one thing for sure that these formulas must be right. But then the fact that E is proportional to the square of the distance between the test charge (Or any other charge, taken from columbs law.) is disobeyed by it (Atleast that's what I think.) I have seen alternate derivations with the same expression. Why is this not obeyed, or is it obeyed over here.

Thank you.
 
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The contribution from each individual charge does obey the inverse square law, but the geometry of the situation leads to the result.
This might help
http://mlg.eng.cam.ac.uk/mchutchon/chargedPlanes.pdf
Notice that the sin θ term increases with the distance from the plate and this counteracts the inverse square relationship.
 
Thanks a tonne :D
 
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