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Question
The equivalent capacitance of the combination shown in the figure is _________ .
Options
C
2 C
C/2
none of these.
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Solution
2C
Since the potential at point A is equal to the potential at point B, no current will flow along arm AB. Hence, the capacitor on arm AB will not contribute to the circuit. Also, because the remaining two capacitors are connected in parallel, the net capacitance of the circuit is given by
`C_"eq" = C + C = 2C`
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