$A$ voltmeter of resistance $R$ is to be used to measure the potential difference across a resistance $r$. In which case will the reading be nearest to the actual potential difference in the absence of the voltmeter?

With a resistance $X$ connected in series with a galvanometer of resistance $100 \Omega$,it acts as a voltmeter of range $0-15 \ V$. To double the range,a resistance of $1500 \Omega$ is to be connected in series with $X$. The value of $X$ in ohm is:

$A$ galvanometer coil has a resistance $90\, \Omega$ and full-scale deflection current $10\, mA$. $A$ $910\, \Omega$ resistance is connected in series with the galvanometer to make a voltmeter. If the least count of the voltmeter is $0.1\, V$,the number of divisions on its scale 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

Consider a moving coil galvanometer $(MCG)$ :
$A :$ The torsional constant in a moving coil galvanometer has dimensions $[ML^2 T^{-2}]$.
$B :$ Increasing the current sensitivity may not necessarily increase the voltage sensitivity.
$C :$ If we increase the number of turns $(N)$ to its double $(2N)$,then the voltage sensitivity doubles.
$D :$ $MCG$ can be converted into an ammeter by introducing a shunt resistance of a large value in parallel with the galvanometer.
$E :$ Current sensitivity of $MCG$ depends inversely on the number of turns of the coil.
Choose the correct answer from the options given below:

Which one of the following modifications may increase the sensitivity of a moving coil galvanometer?
$1^{st}$ Way: By using a spring of smaller torsion constant.
$2^{nd}$ Way: By using a smaller coil.
$3^{rd}$ Way: By using a stronger magnet.
$4^{th}$ Way: By using a coil having fewer number of turns.