The self inductance of an inductor does not depend on the:

The correct answer is Option (4) → current flowing through the inductor

Self-inductance is the flux linked per unit current, \( L = N\Phi/I \). For a long solenoid the flux grows in proportion to the current, so the current cancels and \( L \) depends only on the geometry and the core material.

    \( \displaystyle L = \mu\,n^{2} A\,l \)

Here \( \mu \) is the permeability of the core, \( n \) the number of turns per unit length, \( A \) the area of cross-section and \( l \) the length.

Option (1) number of turns per unit length — Incorrect. \( L \propto n^{2} \); more turns per unit length raise \( L \) strongly.

Option (2) permeability of the medium inside the inductor — Incorrect. \( L \propto \mu \); an iron core raises \( L \) many times.

Option (3) area of cross-section of the inductor — Incorrect. \( L \propto A \); a wider coil links more flux.

Option (4) current flowing through the inductor — Correct. The current changes \( \Phi \) and \( I \) in the same ratio, so \( L \) does not depend on the current.

NCERT (2026-27):
Self-Inductance – “… If we fill the inside of the solenoid with a material of relative permeability μ_r (for example soft iron, which has a high value of relative permeability), then,

    \( \displaystyle L = \mu_r \mu_0 n^2 A l \qquad (6.16) \)

The self-inductance of the coil depends on its geometry and on the permeability of the medium.”