A parallel-plate, air-filled capacitor is being charged. The circular plates have radius 4.00 cm, and at a particular instant the conduction current in the wires is 0.280 A. (a) What is the displacement current density jD in the air space between the plates? (b) What is the rate at which the electric field between the plates is changing? (c) What is the induced magnetic field between the plates at a distance of 2.00 cm from the axis? (d) At 1.00 cm from the axis?
Do i assume displacement current iD = 0.280?
If so, what is iC then?
The Attempt at a Solution
a) jD = iD/A = 0.280/[pi*(0.04)^2] = 55.7 A/m
b) dE/dt = jD/[sigma_0] = 55.7/(8.85*10^-12] = 6.3*10^12
c) B = ([u_o]/2pi)*(r/R^2)*iC where r = radius, R = distance