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, deflections of 60° and 30° are produced. The ratio of the number of turns in A and B is

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, deflections of 60° and 30° 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

Tardigrade Admin · Accepted Answer

As the current and the other factors are same for both the galvanometers N propto tan θ (N1/N2)=( tan 60°/ tan 30°) =(√3/1 / √3) ⇒ (N1/N2)=3

Q. 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, deflections of $6 0^{\circ}$ and $3 0^{\circ}$ are produced. The ratio of the number of turns in $A$ and $B$ is

$1 : 3$

$3 : 1$

$1 : 2$

$2 : 1$

As the current and the other factors are same for both the galvanometers
$N \propto tan θ$
$\frac{N _{1}}{N _{2}} = \frac{t a n 6 0 ^{\circ}}{t a n 3 0 ^{\circ}}$
$= \frac{3}{1/ 3}$
$\Rightarrow \frac{N _{1}}{N _{2}} = 3$

Q. 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, deflections of 60∘ and 30∘ are produced. The ratio of the number of turns in A and B is

1:3

3:1

1:2

2:1