Physics · 2025
JEE Main · 2 April 2025, Shift 2 · Q43
A solenoid having area A and length ' l ' is filled with a material having relative permeability 2. The magnetic energy stored in the solenoid is:
A solenoid having area A and length ' $\displaystyle l$ ' is filled with a material having relative permeability 2. The magnetic energy stored in the solenoid is :
Official answer
From NTA’s final answer key for this paper.
(3)
$\displaystyle \frac{\mathrm{B}^2 \mathrm{Al}}{4 \mu_0}$
More from Electromagnetic Induction
- 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…2025
- A circular current loop of radius R is placed inside square loop of side length L(L ≫ R) such that they are co-planar and their centers coincide. The…2026
- Three identical coils C_1, C_2 and C_3 are closely placed such that they share a common axis. C_2 is exactly midway. C_1 carries current I in…2026
- When a coil is placed in a time dependent magnetic field the power dissipated in it is P. The number of turns, area of the coil and radius of the…2026
- A 30 cm long solenoid has 10 turns per cm and area of 5 cm^2. The current through the solenoid coil varies from 2 A to 4 A in 3.14 s. The e.m.f.…2026
- A metal rod of length L rotates about one end at origin with a uniform angular velocity ω. The magnetic field radially falls off as B(r)=B_o e^-λ r;…2026
- A 1 m long metal rod AB completes the circuit as shown in figure. The area of circuit is perpendicular to the magnetic field of 0.10 T. If the…2026
- A rectangular metallic loop is moving out of a uniform magnetic field region to a field free region with a constant speed. When the loop is partially…2025
JEE Main 2025 Physics question, with the answer from NTA’s final answer key. Where our answers come from.