The sensitivity of a moving coil galvanometer is $s$. If a shunt of $\frac{1}{8}$ of the resistance of the galvanometer is connected to the moving coil galvanometer,what will its new sensitivity be?

$A$ galvanometer of resistance $G$ is shunted by a resistance $S$. To keep the main current in the circuit unchanged,the resistance to be put in series with the galvanometer is

This question has Statement-$I$ and Statement-$II$. Of the four choices given after the statements,choose the one that best describes the two statements.
Statement-$I$: Higher the range,greater is the resistance of an ammeter.
Statement-$II$: To increase the range of an ammeter,an additional shunt needs to be used across it.

Two moving coil galvanometers $A$ and $B$ having identical springs are placed in magnetic fields of $0.25 \ T$ and $0.5 \ T$ respectively. If the number of turns in $A$ and $B$ are respectively $36$ and $48$,and the areas of the coils $A$ and $B$ are $2.4 \times 10^{-3} \ m^2$ and $4.8 \times 10^{-3} \ m^2$ respectively,then the ratio of the current sensitivities of the galvanometers $A$ and $B$ is

What is the value of resistance to double the value of number of turns of coil for a galvanometer? Why?

The range of a voltmeter of resistance $G \ \Omega$ is $V$ volt. The resistance required to be connected in series with it in order to convert it into a voltmeter of range $nV$ volt, will be