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Question
Find the equivalent capacitance of the system shown in figure between the points a and b.

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Solution
Capacitors C1 and C2 above and below ab are connected in series and in parallel with C3.
Thus, the equivalent capacitor between a and b is given by
`C_(eq) = (C_1C_2)/(C_1+C_2) + C_3 + (C_1C_2)/(C_1+C_2)`
`⇒ C_(eq) = C_3 + (2C_1C_2)/(C_1+C_2)`
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