Using Gauss’ law, the electric flux ΦE of a parallel plate capacitor having an area A, and a total charge Q is Where electric field is As the charge Q on the capacitor plates changes with time, so current is given by i = dQ/dt This is the missing term in Ampere’s circuital law. So the total current through the conductor is
i = Conduction current (ic) + Displacement current (id) As Ampere’s circuital law is given by After modification we have Ampere−Maxwell law is given as The total current passing through any surface, of which the closed loop is the perimeter, is the sum of the conduction and displacement current.