Question

What is displacement current why this concept was introduced?

Answer 1

Displacement current is just like pseudo force. When in a parallel plate capacitor different surfaces were taken and value M. Field was calculated it came out to be different for same point. So concept of displacement current was intoduced . now in amperes law instead of conduction current conduction current + displacement current is written. After this modification if we calculate M. Field for same pt. with help of different surfaces value comes out to be same.
Displacement current is directly proportional to change in electric flux

Answer 2

In electromagnetism, displacement current is a quantity appearing in Maxwell's equations that is defined in terms of the rate of change of electricdisplacement field. Displacement current has the units of electric current density, and it has an associatedmagnetic field just as actual currents do.