Question

A condenser having a capacity of `50muF` is charged to a potential of 200 V. If the area of each plate of the condenser is `10cm^(2)` and the distance between the plates is 0.1 mm. The energy per unit volume of the field between the plates is
A. `10^(6)J//m^(3)`
B. `10^(-6)J//m^(3)`
C. `10^(7)J//m^(3)`
D. `10^(-7)J//m^(3)`

Answer 1

Correct Answer - C
`u=(1/2CV^(2))/(A*d)=(CV^(2))/(2Ad)`
`=(50xx10^(-6)xx200xx200)/(2xx10xx10^(-4)xx0.1xx10^(-3))=10^(7)J//m^(3).`