Question

A capacitor of capacitance $50pF$ is charged by $100 V$ source. It is then connected to another uncharged identical capacitor. Electrostatic energy loss in the process is _____ nJ.

Answer 1

Loss in electrostatic energy
$= \frac 12 (\frac 12CV^2)$

$= \frac 12 \times \frac 12 \times 50 \times 10^{-12} \times (100)^2$

$= \frac {500}{4}\ nJ$
$= 125\ nJ$

So, the answer is $125\ nJ$.