Question

Which of the following factors regarding solenoid is/are incorrect?

I.The current flowing in a solenoid is inversely proportional to the strength of the magnetic field: $B\alpha \frac{1}{I}$

II.The number of turns of wire forming the solenoid is directly proportional to the magnetic field $B\alpha n$

III.The magnetic field of a solenoid depends on the nature of material inside the salenoid as $B\alpha \frac{1}{\mu }$ where $\mu$ is the permeability of the material.

• A. I & II
• B. II & III
• C. I & III
• D. All of these

Answer 1

The correct option is C I & III

The magnetic field intensity is directly proportional to the current (I), number of turns of the loop (n) and nature of the material inside the solenoid (B ∝ μ)
Therefore, I and III are incorrect.
Option C is the correct answer.