During the process of charging of a capacitor, a displacement current is produced due to :
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → changing electric field between plates.
Maxwell showed that a changing electric field acts as a source of magnetic field, like a current. This displacement current is \( i_d = \varepsilon_0\,d\Phi_E/dt \).
\( \displaystyle i_d = \varepsilon_0\,\frac{d\Phi_E}{dt} \)
While the capacitor charges, no charge crosses the gap between the plates, but the charge on the plates grows, so the electric field between the plates changes. This changing field carries the displacement current across the gap and keeps the total current continuous.
Why the other options are incorrect
Option (1) the flow of electrons in the conductor. — Incorrect. The flow of electrons in the connecting wires is the conduction current, not the displacement current.
Option (2) oscillating charge between plates — Incorrect. No charge moves across the gap between the plates; the plates only gain or lose charge through the wires.
Option (3) changing magnetic flux between the plates — Incorrect. A changing magnetic flux induces an emf (Faraday’s law); displacement current comes from a changing electric flux.
NCERT (2026-27):
Displacement Current – “… The current carried by conductors due to flow of charges is called conduction current. The current, given by Eq. (8.4), is a new term, and is due to changing electric field (or electric displacement, an old term still used sometimes). It is, therefore, called displacement current or Maxwell’s displacement current.”