Question

Electrostatic energy of 3·5 x 10^-4 J is stored in a capacitor at 700 V. What is the charge on the capacitor?

Answer 1

U = 3.5 × 10^-4J, V =700V 

U =`1/2` Q V

`Q=(2U)/V`

`=(2xx3.5xx10^(-4))/700`

`Q=10^-6C`