A galvanometer shows full scale deflection for a current of 4 mA. It is converted into an ammeter of range from 0 to 8 A by using a shunt. The ratio of resistance of the galvanometer coil to the resistance of the shunt used is nearly:

2000 : 1

The correct answer is Option (1) → 2000 : 1

Given: Galvanometer full scale current $I_g = 4 \times 10^{-3}\,A$ Range of ammeter $I = 8\,A$

Shunt current: $I_s = I - I_g = 8 - 0.004 \approx 7.996\,A$

Condition for parallel connection: $I_g R_g = I_s R_s$

Therefore, $\frac{R_g}{R_s} = \frac{I_s}{I_g}$

$\frac{R_g}{R_s} = \frac{7.996}{0.004} = 1999 \approx 2000$

Final Answer: $\;\;\;\; \frac{R_g}{R_s} \approx 2000$