Relative and absolute potential?

AI Thread Summary
The discussion centers on the concepts of absolute and relative potential in charged capacitors. It clarifies that while charge is absolute, voltage is a measure of potential difference. The experiment with three 100,000V capacitors in series raises questions about charge distribution and the effects of disconnecting the top capacitor. When disconnected, the top capacitor maintains a 100kV difference between its poles but does not retain the absolute voltage offset compared to the lower capacitor. Ultimately, there is no difference in behavior between the disconnected capacitor and the lower capacitor in terms of voltage potential.
Artlav
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Hello.
I've been thinking about potential on charged capacitors, and got confused.

A charge is AFAIK absolute - there is a balance of electrons and protons in matter, which can be biased one way or another.
However, voltage is defined as difference of potential, not an absolute value.
So, 100 volts on the ground is the same as 100V in a middle of a charged thundercloud.

But what kind of charge distribution could there be on a charged capacitor?

The experiment is such:
Take 3 100000V capacitors, and stack them in series.
When charged, top one would have 200kV on one side and 300kV on the other.
These voltages alone are sufficient to produce electric field-related effects, like static cling.

What would happen when that upper capacitor is disconnected from the rest?
Would it maintain the absolute charges - i.e. would there be a 300kV and 200kV worth of static cling?
It would obviously maintain a 100kV difference between the poles, but would the absolute offset remain - that is, is there any difference between it and the lower capacitor in the stack that have 0V and 100kV?
 
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is there any difference between it and the lower capacitor in the stack that have 0V and 100kV?
No. There's not.
 
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