Electric potential at certain point from charged sphere

AI Thread Summary
The discussion centers on calculating the electric potential from a charged sheet, defined by charge density σ = Q/A. The proposed formula for the potential at point X is V = (σX)/ε_0, but there is confusion about why potential decreases with distance from the sheet. It is clarified that this equation is valid only for an infinite sheet, and the potential difference between two points shows a decrease as one moves away from the sheet. The correct expression for potential difference includes a negative sign, indicating the decrease in potential as distance increases. Overall, the behavior of electric potential is consistent with expectations for charged surfaces.
TheCammen
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Let's say I have a sheet of charge that is composed of a certain amount of charged atoms summing up to Q and a certain area A. The charge density would be Q/A = σ. I wish to find the elctrostatic potential from the sheet at point X. I believe that the electric potential should follow the equation:

V = (σX)/ ε_0

However, shouldn't the potential decrease as I travel away from the sheet? If I have a sphere of charge and I travel away from it, then this is the case. Why is this situation different?

EDIT: I meant sheet in the title ofthe post. I just had the sphere idea in my mind at the time!
 
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Hi TheCammen,

1. Strictly speaking, the relation is valid for an infinite sheet only .

2. The potential difference between two points , one at X1 and the other at X2 ( X2>X1) is

V=-σ(X2-X1)/ε0 ( pay attention to the minus sign). And as you see the potential does decrease as you travel away from the sheet.
 

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