Question

A current of ${10}^{-7}$ ampere produces 50 division deflection in a galvanometer. Then its figure of merit will be

• A. ${10}^{-4}amp/div$
• B. ${10}^{-8}amp/div$
• C. ${10}^{-10}amp/div$
• D. $2\times {10}^{-9}amp/div$

Answer 1

The correct option is D $2\times {10}^{-9}amp/div$

Figure of merit is defined as the current which produces a deflection of one scale division in the galvanometer
One division corresponds to $\frac{{10}^{-7}}{50}=2\times {10}^{-9}amp/div$