$A$ galvanometer can be converted into an ammeter by connecting:

The sensitivity of a galvanometer is $60 \text{ division/A}$. When a shunt is used,its sensitivity becomes $10 \text{ division/A}$. If the galvanometer is of resistance $20 \ \Omega$,the value of shunt used is (in $\Omega$)

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 $..... \Omega$.

Moving coil galvanometers $M_{1}$ and $M_{2}$ have resistance, number of turns, area of coil, and magnetic field as follows:
$R_{1}=10 \ \Omega, R_{2}=14 \ \Omega, N_{1}=30, N_{2}=42$
$A_{1}=3.6 \times 10^{-3} \ m^{2}, A_{2}=1.8 \times 10^{-2} \ m^{2}, B_{1}=0.25 \ T, B_{2}=0.50 \ T$
(Spring constants are same for both galvanometers).
The ratio of $(i)$ current sensitivity and (ii) voltage sensitivity for galvanometer ($M_{2}$ to $M_{1}$) is respectively:

$A$ circuit contains an ammeter,a battery of $30\,V$ and a resistance of $40.8\,\Omega$ all connected in series. If the ammeter has a coil of resistance $480\,\Omega$ and a shunt of $20\,\Omega$,the reading in the ammeter will be .................. $A$.

$A$ moving coil galvanometer is converted into an ammeter, reading up to $0.04 \,A$ by connecting a shunt of resistance '$3r$' across it and then into an ammeter reading up to $0.8 \,A$, when a shunt of resistance '$r$' is connected across it. What is the maximum current which can be sent through this galvanometer if no shunt is used (in $\,A$)?