For full scale deflection of total $50$ divisions, $50 \, mV$ voltage is required in a galvanometer. The resistance of the galvanometer, if its current sensitivity is $2 \, div/mA$, will be $..... \Omega$.

$A$ microammeter has a resistance of $100\,\Omega$ and a full-scale range of $50\,\mu A$. It can be used as a voltmeter or a higher-range ammeter provided a resistance is added to it. Pick the correct range and resistance combination$(s)$.

$A$ 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 $.

In a moving coil galvanometer,to make the field radial,what is done?

Two moving coil meters,$M_{1}$ and $M_{2}$ have the following particulars:
$R_{1}=10 \,\Omega, \quad N_{1}=30$
$A_{1}=3.6 \times 10^{-3} \,m^{2}, \quad B_{1}=0.25 \,T$
$R_{2}=14 \,\Omega, \quad N_{2}=42$
$A_{2}=1.8 \times 10^{-3} \,m^{2}, \quad B_{2}=0.50 \,T$
(The spring constants are identical for the two meters). Determine the ratio of
$(a)$ current sensitivity and
$(b)$ voltage sensitivity of $M_{2}$ and $M_{1}$.

An ideal ammeter and an ideal voltmeter have resistances of . . . . . . $\Omega$ and . . . . . . $\Omega$ respectively.