$A$ galvanometer of resistance $20 \,\Omega$ is to be converted into an ammeter of range $1 \, A$. If a current of $1 \, mA$ produces full scale deflection,the shunt required for the purpose is ................ $\Omega $.

What is a galvanometer? Give its applications.

When a resistance of $5\,\Omega$ is shunted with a moving coil galvanometer,it shows a full scale deflection for a current of $250\,mA$. However,when a $1050\,\Omega$ resistance is connected with it in series,it gives full scale deflection for $25\,V$. The resistance of the galvanometer is $......\,\Omega$.

In order to pass $10\,\%$ of the main current through a moving coil galvanometer of $99\,\Omega$,the resistance of the required shunt is ............ $\Omega$.

$A$ voltmeter with internal resistance of $x\text{ }\Omega$ can be used to measure up to $20\text{ V}$. In order to increase its measuring range to $30\text{ V}$, the required modification is to . . . . . . .

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