The potential differences that must be applied across the parallel and series combination of 3 identical capacitor(C
The potential differences that must be applied across the parallel and series combination of 3 identical capacitor(C

The correct option is option (C) \frac{1}{3}.

Let C be the capacity of each capacitor. The equivalent capacitance of three capacitors in parallel combination will be C_{p}=3 C and in series combination \mathrm{C}_{\mathrm{s}}=\frac{C}{3}Let V_{P} be the potential difference in parallel combination and V_{s} in series combination then the energy stored in the same in the two cases.
\begin{array}{l} \therefore \frac{1}{2} C_{p} V_{p}^{2}=\frac{1}{2} C_{s} V_{s}^{2} \\ \therefore \frac{V_{p}^{2}}{V_{s}^{2}}=\frac{C_{s}}{C_{p}}=\frac{C}{3} \cdot \frac{1}{3 C}=\frac{1}{9} \\ \therefore \frac{V_{p}}{V_{s}}=\frac{1}{3} \end{array}