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

Hint:

In a moving coil galvanometer, deflection is proportional to the current passing through the coil.

Answer 1

The Correct Option is B

Analysis of the provided assertion and reason requires verification of their accuracy and interrelation.

Assertion (A): "Deflection in a galvanometer is directly proportional to the current passing through it." This statement is accurate. A galvanometer operates on the principle that a current-carrying coil within a magnetic field experiences a magnetic torque, inducing rotation. The extent of deflection directly correlates with the current magnitude.

Reason (R): "The coil of a galvanometer is suspended in a uniform radial magnetic field." This statement is also accurate. The design of a galvanometer incorporates a uniform radial magnetic field to ensure consistent sensitivity throughout the coil's rotational range.

Although both the assertion and the reason are factually correct, the reason describes a design characteristic contributing to uniform sensitivity. It does not, however, provide the direct causal link for the proportionality between deflection and current. This proportionality stems primarily from the magnetic torque experienced by the coil, which is itself proportional to the current. Consequently, the correct classification is:

Both Assertion (A) and Reason (R) are true, but Reason (R) does not correctly explain Assertion (A).