Q17 of 26 Page 1

A. Find equivalent capacitance between A and B in the combination given below. Each capacitor is of 2 μF capacitance.


B. If a dc source of 7 V is connected across AB, how much charge is drawn from the source and what is the energy stored in the network?


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


Conclusions: -


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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