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Question
Consider the situation shown in figure. The switch is closed at t = 0 when the capacitors are uncharged. Find the charge on the capacitor C1 as a function of time t.

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Solution
The two capacitors are connected in series. Their equivalent capacitance,
\[C_{eqv} = \frac{C_1 C_2}{C_1 + C_2}\]
The growth of charge in the capacitors,
\[q = C_{eqv} \epsilon\left( 1 - e^{- \frac{1}{r C_{eqv}}} \right)\]
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