Question

A solenoid 30 cm long is made by winding 2000 loops of wire on an iron rod whose cross-section is \( 1.5 \, \text{cm}^2 \). If the relative permeability of the iron is 6000, what is the self-inductance of the solenoid?

• A. 1.5 H
• B. 2.5 H
• C. 3.5 H
• D. 0.5 H

Hint:

The self-inductance of a solenoid depends on its number of turns, length, and the properties of the material.

Answer 1

The Correct Option is A

The self-inductance \( L \) of a solenoid is given by the formula: \[ L = \frac{\mu_0 \mu_r N^2 A}{l} \] Where \( \mu_0 \) is the permeability of free space, \( \mu_r \) is the relative permeability, \( N \) is the number of turns, \( A \) is the cross-sectional area, and \( l \) is the length of the solenoid.