In the given figure,an ammeter $A$ consists of a $240 \Omega$ coil connected in parallel to a $10 \Omega$ shunt. The reading of the ammeter is . . . . . . $mA$.

When an additional resistance $1980 \ \Omega$ is connected in series with a voltmeter,each scale division has $100$ times larger value. The resistance of the voltmeter is (in $\Omega$)

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

To send $10 \%$ of the main current through a moving coil galvanometer of resistance $99 \Omega$,the shunt required is . . . . . . . (in $\Omega$)

Write the equation for the series resistance required to increase the voltage range of a galvanometer by a factor of $n$.

$A$ galvanometer of resistance $30 \Omega$ is connected to a battery of emf $2 \text{ V}$ with $1970 \Omega$ resistance in series. $A$ full-scale deflection of $20$ divisions is obtained in the galvanometer. To reduce the deflection to $10$ divisions,the total resistance in series required is: (in $\Omega$)