Voltage between two different charges

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The discussion centers on calculating voltage between two different charges in a capacitor setup. It starts with the basic formula for voltage, V = Charge / Capacitance, but raises questions about how to apply this when the charges are unequal. Participants suggest using the electric field formula, V = -∫ E dl, to derive voltage, emphasizing the need to understand the electric field created by differing charge densities. There is uncertainty about how to define the electric field when dealing with two different charge densities, and it is noted that the shape and type of capacitor may influence the calculations. The conversation highlights a need for further clarification on the relationship between voltage and varying charge densities.
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Voltage = Charge / Capacitance.

This assumes that the capacitor has +Q charge on one side and -Q charge on the other side.

What if you have two different charges?

I mean in terms of static electricity, if you have a piece of metal with one charge, and another piece of metal with another charge, the capacitance between them depends on their distance from each other and their volume... But they have two different charges.

How do you find the voltage?

Thank you,
Veniamin
 
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I think by using the formula V=-\int \vec E d \vec l so you'd have to calculate the electric field of the charged capacitor.
 
fluidistic said:
I think by using the formula V=-\int \vec E d \vec l so you'd have to calculate the electric field of the charged capacitor.

Indeed, after spending a while on http://en.wikipedia.org/wiki/Capacitor#Parallel_plate_model", I found that E = +- charge density / some constant ..
It goes on taking the integral of E * something = Voltage

But, I don't understand what E equals if you have two different charge densities.

Does anybody?

Note that it seems safe to assume that charge is proportional charge density, so we are still trying to figure out the original problem:
What voltage do you get based on two different charges?
 
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LiteHacker said:
Indeed, after spending a while on http://en.wikipedia.org/wiki/Capacitor#Parallel_plate_model", I found that E = +- charge density / some constant ..
It goes on taking the integral of E * something = Voltage

But, I don't understand what E equals if you have two different charge densities.

Does anybody?

Note that it seems safe to assume that charge is proportional charge density, so we are still trying to figure out the original problem:
What voltage do you get based on two different charges?
You'd have to find out \vec E, I believe but not 100% sure. This value may depends on the type of capacitor and its shape.
I'll wait someone else to enlighten us.
 
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