Regarding self-inductance: A. The self-inductance of the coil depends… | JEE Main 2025 (23 Jan, Shift 1)

Q25JEE Main 2025 · 23 JAN · SHIFT 1Easy

Self-Inductance & Energy

Regarding self-inductance:

A. The self-inductance of the coil depends on its geometry.

B. Self-inductance does not depend on the permeability of the medium.

C. Self-induced e.m.f. opposes any change in the current in a circuit.

D. Self-inductance is electromagnetic analogue of mass in mechanics.

E. Work needs to be done against self-induced e.m.f. in establishing the current. Choose the correct answer from the options given below:

Show answer and solution

Answer: (c)

A: true, $L$ depends on number of turns, size and shape of the coil.
B: false, $L = \mu N^2A/l$ depends on the permeability $\mu$ of the medium (core).
C: true, by Lenz's law the self-induced emf opposes the change of current.
D: true, $L$ resists change of current just as mass resists change of velocity ( $\tfrac12 LI^2 \leftrightarrow \tfrac12 mv^2$ ).
E: true, work done against the back emf is stored as $\tfrac12 LI^2$ .
So the answer is (c) A, C, D, E only.

Self-Inductance & Energy question from JEE Main 2025 (23 Jan, Shift 1)