(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Capacitors [itex] C_1=6μF [/itex] and [itex] C_2=2μF [/itex] are first charged by connecting them in parallel across a [itex] 250V [/itex] battery. The capacitors are then disconnected from the battery and connected positive plate to negative plate and negative plate to positive plate. Calculate their charges after the switches are closed (figure attached).

The answer is given: [itex] Q_1=750μC [/itex] and [itex] Q_2=250μC [/itex].

2. Relevant equations

[itex] Q=CV [/itex] Where [itex] Q [/itex] is the charge, [itex] C [/itex] is the capacitance and [itex] V [/itex] is the voltage.

3. The attempt at a solution

I'm really at a loss in how to approach this problem. I'm not even sure whether the capacitors are considered to be in series or in parallel. Since the positive plates are connected to the negative ones I assumed it was in series but in series the charges on capacitors are the same which can't be right since for the final answer the charges between the two are different. I then tried it if the capacitors were in parallel, but that would mean the voltages of both capacitors must be the same as well, meaning that the final charges should equal the original charges on the capacitors since they were both charged to a voltage of 250V, which is also wrong.

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# Charges of two capacitors in a circuit

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