Question

In a half deflection experiment, a galvanometer shows 30 divisions for a current of 3 × 10⁻⁴ A. Find its figure of merit K.

Options

• 1 × 10⁻⁵ A/div

• 9 × 10⁻³ A/div

• 1 × 10⁻⁴ A/div

• 3 × 10⁻⁴ A/div

Answer 1

1 × 10⁻⁵ A/div

Explanation:

Figure of merit K = \[\frac {I}{θ}\] = \[\frac {3×10^−4}{30}\] = 1×10⁻⁵ A/div. A smaller figure of merit indicates a more sensitive galvanometer, as less current is needed to produce one division of deflection on the scale.