Question

Assertion: The magnetic field produced by a current carrying solenoid is independent of its length and cross-sectional area.
Reason: The magnetic field inside the solenoid is uniform.

• A. If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
• B. If both Assertion and Reason are true but the Reason is not the correct explanation of the Assertion.
• C. If Assertion is true but Reason is false.
• D. If both Assertion and Reason are false.

Answer 1

Answer: (B)

The magnetic field due to solenoid having $n$ number of turns/metre and carrying current $I$ is

It is obvious that magnetic field is independent of length and area.
Also, magnetic field is uniform inside the solenoid.