Q. 175.0( 8 Votes )
A) The capacitors between nodes P, R, S are in parallel combination as the nodes P, S and R, T are short circuited respectively, so,
The Equivalent resistance between P and T is C + C + C = 3C (Parallel combination of capacitors), now three capacitors C, 3C, and C are in series, So, net equivalent capacitance is,
B) The charge drawn from the battery is, q = CeqV
The energy stored in the network of capacitors is,
E = 21 μJ
The net equivalent capacitance of the network is 6/7 μF
The net charge drawn from the source is 6 μC
The total energy stored in the network of capacitors is 21 μJ
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