Does distance inbetween the plates of a capacitor have an effect on its charge?

AI Thread Summary
The distance between the plates of a capacitor affects its charge differently depending on whether it is connected to a battery. When connected, increasing the distance doubles the voltage while halving the capacitance, resulting in a constant charge. Conversely, if the capacitor is disconnected from the battery, the charge remains constant, but the voltage changes as the distance increases. Thus, while connected, the charge varies with distance, and when disconnected, the charge remains fixed. Understanding these principles is crucial for analyzing capacitor behavior in electrical circuits.
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You have a parallel plate capacitor, each with opposite charge Q, connected to a battery of some voltage.

What I'm wondering, is does the distance inbetween these plates have an effect on their charge, while connected to the battery? What about if the distance was changed after being disconnected from the battery?

What I think, is if the distance was doubled (while connected to the battery) the V=Ed would double, the C=(elipson)(A)/d would half, therefore the Q=CV would stay the same.

And if the distance was doubled after disconnected from the battery, V stays fixed, so does C, and therefore Q does as well.

Are those assumptions correct?
 
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It's the other way around. If the battery stays connected V stays the same and therefore the charge changes. If you disconnect the battery the charge stays the same since there is no way for the charge to flow away. So V changes.
 
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