Is total capacitor energy 2400 J if each plate has 1200 J charge?

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leelsund
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I guess this is a simple question and I can't find clarification on it any where

If the total charge on each plate of a parallel plate capacitor is 1200 joules then is the total energy stored in that capacitor 2400 joules. Lol might seem dumb but I just want to make sure this was correct

Thanks
 
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leelsund said:
the total charge on each plate of a parallel plate capacitor is 1200 joules then
Charge is measured in units of coulombs, not joules.
 


DaleSpam said:
Charge is measured in units of coulombs, not joules.

k then does the charge on each plate = total charge

so 1200 on one plate 1200 on the other = 2400
 


Capacitor charge Q is defined so that there is charge separation with +Q on the positive plate and also -Q on the negative plate, when we say that the capacitor voltage is V=Q/C and the energy stored is (1/2)CV^2.

(Note that a total for +Q and -Q would always be zero.)
 
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mikelepore said:
Capacitor charge Q is defined so that there is charge separation with +Q on the positive plate and also -Q on the negative plate, when we say that the capactor voltage is V=Q/C and the energy stored is (1/2)CV^2.

(Note that a total for +Q and -Q would always be zero.)

total energy stored in a capacitor is split between the 2 plates. So say the capacitor stores 2 joules of energy does each plate hold 1 joule of charge.
 


Don't think of each plate holding half of the energy. Think of the energy being in the fact that +Q and -Q are attracted to each other but not allowed to move toward each other because of the insulation in the spacing.
 


mikelepore said:
Don't think of each plate holding half of the energy. Think of the energy being in the fact that +Q and -Q are attracted to each other but not allowed to move toward each other because of the insulation in the spacing.

The question I have is a parallel plate capacitor holds a charge of 1200 joules on each plate. It has a potential difference of 110 volts applied to it what is the capacitance of the capacitor in farads
 


What DaleSpam said above. If the question says "a charge of 1200 joules" the question is incorrectly worded. I would ask the writer of the question if they mean "a charge of 1200 coulombs." If they say yes, then Q is 1200 coulombs.

I have never heard anyone refer to energy per plate.