- #1
musicboy
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Member advised to use the homework template for posts in the homework sections of PF.
Hi
I am confused about an example in my textbook related to charge stored by a capacitor
A 100 uF capacitor and a 700 uF capacitor are placed in series, along with a cell of 3V.
Calculate the p.d. across the 100 uF capacitor.
The book states the solution as follows:
"Using the reciprocal formula, the capacitance of the whole circuit is 87.5 uF.
This means the total charge stored Q = VC = 3 * 87.5e-6 = 2.63e-4
The total charge stored is equal to the charge stored by the 100 uF capacitor, which is equal to the charge stored by the 700 uF capacitor.
So V = Q/C = 2.63e-4/100e-6 =2.6V"
I understand all of this apart from the last section. I understand that the charge stored on both capacitors will be the same, but I do not understand how they can both be equal to the total charge - surely the total charge is the sum of the charges stored on both capacitors?
Any help much appreciated.
I am confused about an example in my textbook related to charge stored by a capacitor
A 100 uF capacitor and a 700 uF capacitor are placed in series, along with a cell of 3V.
Calculate the p.d. across the 100 uF capacitor.
The book states the solution as follows:
"Using the reciprocal formula, the capacitance of the whole circuit is 87.5 uF.
This means the total charge stored Q = VC = 3 * 87.5e-6 = 2.63e-4
The total charge stored is equal to the charge stored by the 100 uF capacitor, which is equal to the charge stored by the 700 uF capacitor.
So V = Q/C = 2.63e-4/100e-6 =2.6V"
I understand all of this apart from the last section. I understand that the charge stored on both capacitors will be the same, but I do not understand how they can both be equal to the total charge - surely the total charge is the sum of the charges stored on both capacitors?
Any help much appreciated.