Question

The data given below shows the variation of potential with charge during charging of a condenser.

Q	0μc	1μc	2μc	3μc	4μc	5μc
V	OV	5V	10V	15V	20V	25V

1. Draw a graph with charge along the Y axis and potential along the X axis. Estimate capacity of the condenser from the graph.

2. Estimate the energy stored in the condenser from the graph.

Answer 1

C = \(\frac{dQ}{dV}=\frac{5\times10^{-6}}{25}\) = \(\frac{1}{5}\times10^{-6}\) = 0.2μF

2.  Area enclosed by the graph represents total energy = 1/2 QV = 1/2 × 5 × 10^-6 × 25 = 62.5 × 10^-6 J