What is the total charge stored by parallel plate capacitors?

AI Thread Summary
The discussion focuses on the total charge stored by parallel plate capacitors, emphasizing that after connecting to a battery, the capacitors reach maximum charge, denoted as Q_1 and Q_2. The total charge, Q_tot, is the sum of these individual charges. A key point raised is the misconception that Q_1 and Q_2 would be zero after charging; instead, the charges on the plates are equal in magnitude but opposite in sign. The charge stored refers to the magnitude on each plate, while the total charge across both plates remains zero. Understanding this concept is crucial for grasping capacitor behavior in circuits.
Bashyboy
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Hello,

I am currently reading about what has been alluded to in the title of this thread. I attached a diagram, as it will be of some help.

Okay, in my textbook it says:

After the battery is attached to the circuit, the capacitors quickly reach their
maximum charge. Let’s call the maximum charges on the two capacitors Q_1 and Q_2. The total charge Q_{tot} stored by the two capacitors is the sum of the charges on the individual capacitors: Q_{tot} = Q_1 + Q_2.

My question is, wouldn't Q1 and Q2 both be zero, once the plates have been charged; that is, the electrons flow from the negative terminal into the plate on the right side, building up negative charge, which then repels all of the electrons in the adjacent plate, causing positive charge to build up?
 

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Bashyboy said:
My question is, wouldn't Q1 and Q2 both be zero, once the plates have been charged; that is, the electrons flow from the negative terminal into the plate on the right side, building up negative charge, which then repels all of the electrons in the adjacent plate, causing positive charge to build up?
When they speak of the charge stored on a capacitor, they mean the magnitude of the charge on each plate. (The total charge on both plates is of course zero.)
 
Oh, okay. Thanks!
 
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