When a resistance of $100 \Omega$ is connected in series with a galvanometer of resistance $G$,its range is $V$. To double its range,a resistance of $1000 \Omega$ is connected in series. The value of $G$ is (in $\Omega$)

$A$ moving coil galvanometer has a coil with $175$ turns and an area of $1 \, cm^2$. It uses a torsion band with a torsion constant of $10^{-6} \, N \cdot m/rad$. The coil is placed in a magnetic field $B$ parallel to its plane. The coil deflects by $10^{\circ}$ for a current of $1 \, mA$. The value of $B$ (in Tesla) is approximately:

$A$ galvanometer of resistance $25\,\Omega$ gives full-scale deflection for a current of $10\,mA$. It is to be converted into a voltmeter of range $100\,V$ by connecting a resistance $R$ in series with the galvanometer. The value of resistance $R$ in $\Omega$ is:

$A$ galvanometer has a $50$ division scale. The battery has no internal resistance. It is found that there is a deflection of $40$ divisions when $R = 2400\,\Omega$. The deflection becomes $20$ divisions when the resistance taken from the resistance box is $4900\,\Omega$. Then we can conclude:

In a moving coil galvanometer,two moving coils $M_1$ and $M_2$ have the following particulars:
$R_1 = 5 \ \Omega, N_1 = 15, A_1 = 3.6 \times 10^{-3} \ m^2, B_1 = 0.25 \ T$
$R_2 = 7 \ \Omega, N_2 = 21, A_2 = 1.8 \times 10^{-3} \ m^2, B_2 = 0.50 \ T$
Assuming that the torsional constant of the springs is the same for both coils,what will be the ratio of the voltage sensitivity of $M_1$ and $M_2$?

When a galvanometer is shunted by a resistance $s$,its current capacity increases $n$ times. If the same galvanometer is shunted by another resistance $s_1$,its capacity will increase to $n_1$ times the original current. The value of $n_1$ is