In a galvanometer,the deflection becomes one half when the galvanometer is shunted by a $20\,\Omega$ resistor. The galvanometer resistance is ............... $\Omega$.

$A$ 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:

Two tangent galvanometers $A$ and $B$ are identical except in their number of turns. They are connected in series. On passing a current through them,deflections of $60^{\circ}$ and $30^{\circ}$ are produced. The ratio of the number of turns in $A$ and $B$ is

The coil of a moving coil galvanometer has an effective area of $4 \times 10^{-2} \, m^2$. It is suspended in a magnetic field of $5 \times 10^{-2} \, Wb \, m^{-2}$. If the deflection in the galvanometer coil is $0.2 \, rad$, when a current of $5 \, mA$ is passed through it, then

$A$ maximum current of $0.5 \ mA$ can pass through a galvanometer of resistance $15 \ \Omega$. The resistance to be connected in series to the galvanometer to convert it into a voltmeter of range $0-10 \ V$ is (in $\Omega$)

$A$ galvanometer of resistance $100 \Omega$ gives full scale deflection for a current of $1 \text{ mA}$. It is converted into an ammeter of range $0 - 10 \text{ A}$. The shunt required is: (in $\text{ }\Omega$)