To convert a $800\, mV$ range millivoltmeter of resistance $40\,\Omega$ into an ammeter of $100\, mA$ range,the resistance to be connected as a shunt is .............. $\Omega$.

$A$ galvanometer of resistance $G$ is shunted by a resistance of $5 \Omega$. To keep the main current in the circuit unchanged,the resistance to be put in series with the same galvanometer is

The scale of a galvanometer is divided into $160$ equal divisions. The galvanometer shows full scale deflection of $16$ mA and maximum voltage is $80$ mV. Now the range is changed so that the galvanometer reads $160$ $V$. The required resistance to be connected is

The current sensitivity of a moving coil galvanometer is increased by $25 \%$. This increase is achieved only by changing the number of turns of the coils and the area of the cross-section of the wire while keeping the resistance of the galvanometer coil constant. The percentage change in the voltage sensitivity will be $...........\%$

Mark out the correct options.

The graph which represents the relation between the total resistance $R$ of a multi-range moving coil voltmeter and its full-scale deflection $V$ is