Question

Explain Maxwell's displacement current and write its equation. What is the phase difference between it and the conduction current? 
 

Hint:

Maxwell’s displacement current accounts for the changing electric field and ensures that the magnetic field is continuous even in regions without free charge carriers.

Answer 1

Maxwell's displacement current is a term added by Maxwell in the Ampere's law to account for the changing electric field in a capacitor or any region where the electric field is changing with time. The displacement current density \( J_D \) is given by: \[ J_D = \epsilon \frac{\partial E}{\partial t}, \] where \( \epsilon \) is the permittivity of the medium, and \( \frac{\partial E}{\partial t} \) is the time rate of change of the electric field. The displacement current causes a magnetic field in the same way as conduction current, ensuring continuity of current even in regions without free charge carriers. The displacement current and conduction current are in phase, meaning they oscillate together.