When a galvanometer is shunted by a resistance $S$, its current capacity increases $n$ times. If the same galvanometer is shunted by another resistance $S'$, its current capacity will increase to $n'$. The value of $n$ in terms of $n'$, $S$, and $S'$ is

An ammeter of $100 \, \Omega$ resistance gives full-scale deflection for a current of $10^{-5} \, A$. The shunt resistance required to convert it into an ammeter of $1 \, A$ range will be:

Explain the difficulties encountered when using a galvanometer directly as an ammeter.

The ratios of the voltage sensitivities,resistances and areas of the coils of two moving coil galvanometers $A$ and $B$ are $4:3$,$3:4$ and $1:2$ respectively. If the number of turns of the coil of galvanometer $A$ is $200$,then the number of turns of the coil of galvanometer $B$ is (All other quantities remain same in both the cases)

Two identical galvanometers are converted into a voltmeter and a millivoltmeter. As compared to the series resistance of the voltmeter,the series resistance of the millivoltmeter will be

$A$ galvanometer coil has a resistance of $12\,\Omega$ and the meter shows full-scale deflection for a current of $3\,mA$. To convert it into a voltmeter of range $0-18\,V$,what resistance should be added and how?