Question

Two tangent galvanometers $A$ and $B$ are identical except in their number of turns. They are connected in series. On passing a current through them, deflection of ${60}^o$ and ${30}^o$ are produced. The ratio of the number of turns in $A$ and $B$ is

• A. $1:3$
• B. $3:1$
• C. $1:2$
• D. $2:1$

Answer 1

The correct option is D $2:1$

$i=\frac{K}{NAB}\varphi$

$\frac{N_A}{N_B}=\frac{{\varphi }_A}{{\varphi }_B}=2:1$