Calculating Charge in a Parallel Connection of Capacitors

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SUMMARY

The discussion focuses on calculating the charge in a parallel connection of capacitors, specifically 11.1uF and 1.9uF, charged across a 333V battery. The equivalent capacitance (Ceq) is determined to be 13uF, leading to a total charge (Qtotal) of 0.004329 C. The user attempts to apply an equilibrium theorem to find the charge on the first capacitor but encounters confusion regarding the maximum charge and the subsequent connection of capacitors in series. The problem also involves analyzing the charge distribution when the capacitors are reconnected with opposite polarities.

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Homework Statement


Capacitors of 11.1uF and 1.9uF are charged as a parallel combination across a 333V battery. The capacitors are disconnected from the battery and from each other. They are then connected positive to negative plate and negative to positive plate. Find the resulting charge on the first capacitor in units uC.


Homework Equations


1. Ceq = C1 + C2 parallel capacitance C1=11.1uF C2=1.9uF
2. Qtotal=V * Ceq

The Attempt at a Solution


1. Ceq = 11.1uF + 1.9uF = 13uF
2. Qtotal = 333 * 13uF = .004329 C

i tried using an equilibrium theorem:
(Qtot / Ceq) = (Qtot - q1) / 11.1uF -> .004329 / 13e-6 = (.004329 - q1) / 11.1e-6
with q1 = .0080253C but it's bigger than q= 333V * 11.1uF = .036963 so i don't think it's correct because that would be the max charge, right?

after this point do i treat it as capacitors in series or what?

part B of the problem states they are charged in series and then disconnected from the battery and connected positive plate to positive place and negative to negative plate

sorry if I'm overlooking something obvious.
thanks
david
 
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Find the original charge on each capacitor. When they are reconnected, what's the total charge on both capacitors? When reconnected, what's the same across each capacitor? Use that to figure out how the charge rearranged itself upon reconnection.
 

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