Why Capacitors Store Half The Charge They Are Given

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Capacitors store energy based on the equations Q=CV and E=0.5CV², indicating that while all charge is delivered, only half of the energy is stored. The discussion highlights confusion between charge and energy, clarifying that the charge delivered is fully stored, but the energy stored is half of what is supplied. The relationship between capacitance, charge, and voltage is emphasized through the equations. The Q-V graph is essential for understanding energy storage in capacitors. Ultimately, the conversation seeks to clarify the distinction between charge and energy in the context of capacitor functionality.
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I have been studying capacitors this week and learned two equations. One is Q=CV and the other is Q=0.5CV. The latter equation is derived from C-V graph. From this it shows that half the charge delivered is stored. I am very curious to know where the other half of the charge go and why is the charge stored exactly half of the charge supplied? How is the half of the charge which is not stored used?
 
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Dark Red Rose said:
I have been studying capacitors this week and learned two equations. One is Q=CV and the other is Q=0.5CV. The latter equation is derived from C-V graph. From this it shows that half the charge delivered is stored. I am very curious to know where the other half of the charge go and why is the charge stored exactly half of the charge supplied? How is the half of the charge which is not stored used?
The charge stored in a capacitor of capacitance, C, with a potential difference, V, across its plates is Q = CV .

The energy stored in such a capacitor is (1/2)CV2. That doesn't mean that the charge is (1/2)CV.
 
Dark Red Rose said:
From this it shows that half the charge delivered is stored. I am very curious to know where the other half of the charge go and why is the charge stored exactly half of the charge supplied? How is the half of the charge which is not stored used?

Replace the word 'charge' in this paragraph with the word 'energy' and you will then have a good question. As Sammy was implying, all of the charge delivered is stored.

P.S. you have an awesome name. and welcome to physics forums!
 
You have your terms mixed up
C = Q/V or Q = C x V or V = Q/C...these give the relationships between Q, C and V.
The graph I think you are talking about is Q against V (not C ~ V)
This graph enables you to calculate the ENERGY stored on the capacitor, the ENERGY equations are
E 0.5QV...or 0.5CV^2 or 0.5Q^2/C
 
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