Question

Assertion (A): The deflection in a galvanometer is directly proportional to the current passing through it.
Reason (R): The coil of a galvanometer is suspended in a uniform radial magnetic field.

• A. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A)
• B. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A).
• C. Assertion (A) is true, but Reason (R) is false.
• D. Assertion (A) is false and Reason (R) is also false.

Hint:

The deflection in a galvanometer is directly related to the current, but the suspension of the coil in a uniform magnetic field is not the only reason for this relationship.

Answer 1

The Correct Option is B

To resolve this assertion-reason question, we must evaluate the veracity of each statement and their interrelationship.

Assertion (A): A galvanometer's deflection is directly proportional to the current flowing through it.
This assertion posits a foundational principle of galvanometer operation. A current through the galvanometer coil generates a torque within the magnetic field, leading to a deflection that is typically proportional to the current.
Consequently, the assertion is true.

Reason (R): The galvanometer coil is suspended within a uniform radial magnetic field.
This reason outlines a characteristic construction of a galvanometer: the coil is situated in a uniform radial magnetic field. This configuration ensures that the torque on the coil is proportional to the current, irrespective of its orientation, as the angle between the coil's plane and the magnetic field remains constant.
Therefore, the reason is also true.

Although the reason accurately describes an element of the galvanometer's design, it does not directly explain the proportionality of deflection to current. The proportional deflection arises from the linear relationship between current, magnetic field, and torque, rather than solely from the coil's placement in a radial field.

Accordingly, the definitive conclusion is: Both Assertion (A) and Reason (R) are true, but Reason (R) does not correctly explain Assertion (A).