Displacement Current — CapacitorHardQuestion 20226
Question
Between the plates of a charging capacitor, the magnetic field is produced by:
- AConduction current through the plates
- BDisplacement current (ε₀ dE/dt)Correct
- CDirect flow of electrons through the gap
- DResistance of the dielectric
Correct answer
Displacement current (ε₀ dE/dt)
Explanation
No conduction current flows between the plates, but the changing electric field produces a displacement current id = ε₀(dΦE/dt) = ε₀A(dE/dt). This displacement current produces a magnetic field between the plates, just as conduction current does outside.