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.

Options

• Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).

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

• Assertion (A) is true, but Reason (R) is false.

• Assertion (A) is false and Reason (R) is also false.

Answer 1

Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).

Explanation:

Assertion (A) is correct. A galvanometer’s deflection (θ) is proportional to the current (I) that passes through it. θ ∝ I. The coil’s torque is proportional to its current.

Reason (R) is true. A galvanometer’s coil is suspended in a uniform radial magnetic field, resulting in a torque that is proportional to the sine of the angle between the coil and the field. The torque is proportional to the current due to the constant sine term in the radial field.

Reason (R) correctly explains Assertion (A). The uniform radial magnetic field assures that the deflection is linearly proportional to the current, resulting in the equation θ ∝ I.