Question

Considering the case of a parallel plate capacitor being charged, show how one is required to generalize Ampere's circuital law to include the term due to displacement current.

Answer 1

The space between the capacitor consists of an insulator. Hence, no actual transfer of charge occurs in this region. Current flows in the circuit during the charging of a capacitor. This demands the need of the presence of a displacement current in the capacitor resulting in a magnetic field.

$\int B.dl={\mu }_{o}I$

Here $I$ is the sum of conduction and displacement currents.