Practice portal › Electromagnetic Waves › Displacement Current
Asked in GUJCET 2020 · Displacement current equals conduction current
Idea: Ampere's law applied to a charging capacitor gives two different answers for two surfaces bounded by the same loop, because no charge crosses the gap between the plates.
Maxwell removed the contradiction by adding a term built from the changing electric flux in the gap: i_d = ε₀(dΦ_E)/(dt).
So wherever the electric field, and with it the electric flux, changes with time, there is a displacement current -- even in vacuum, with no charge moving at all.
The source of displacement current is therefore a changing electric field.
Reading this solution needs no sign-in. You only sign in to practise against the clock and keep your progress.
Practise this with a timer