Question

The ratio of the resistances of a galvanometer and a shunt connected to it is 50 : 1. The ratio of the currents in the galvanometer and the shunt when the combination is used as an ammeter is

• A. 49 : 1
• B. 1 : 49
• C. 1 : 50
• D. 50 : 1

Answer 1

Answer: (C)

1 : 50

Given: Ratio of resistances of a galvanometer and shunt is $50:1$

In case of ammeter the shunt and galvanometer are connected in parallel.

According to ohms law: $I=\frac{V}{R}$

$V$ across the shunt and galvanometer is same as both are in parallel.

Current flowing in the galvanometer $=\frac{V}{50R}$

Current flowing in the shunt $=\frac{V}{R}$

So, the ratio of currents flowing through the galvanometer and the shunt is $=\frac{\frac{V}{50R}}{\frac{V}{R}}=\frac{1}{50}$