The displacement current is due to ____.

The correct answer is Option (1) → the time varying electric flux

Maxwell showed that a changing electric field produces a magnetic field just as a conduction current does. The equivalent current, called the displacement current, is

    \( \displaystyle i_d = \varepsilon_0\,\frac{d\phi_E}{dt} \)

It exists wherever the electric flux changes with time, for example between the plates of a charging capacitor, where no charges flow.

Option (2) the flow of conduction charges — Incorrect. That is the conduction current.

Option (3) time varying magnetic fields — Incorrect. A changing magnetic flux produces an induced emf (Faraday’s law), not a displacement current.

Option (4) static electric fields — Incorrect. If the field does not change, \( d\phi_E/dt = 0 \) and there is no displacement current.

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.”