An ammeter with internal resistance $90\,\Omega$ reads $1.85\,A$ when connected in a circuit containing a battery and two resistors $700\,\Omega$ and $410\,\Omega$ in series. The actual current in the circuit (without the ammeter) will be:

$A$ galvanometer may be converted into an ammeter or a voltmeter. In which of the following cases will the resistance of the device so obtained be the largest?

$A$ galvanometer has $30$ divisions and a current sensitivity of $20 \, \mu A$ per division. Its resistance is $25 \, \Omega$. How will you convert this galvanometer into a voltmeter of $1 \, V$ range? (Find the series resistance in $\Omega$)

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 $M_2$?

In a galvanometer,$5 \%$ of the total current in the circuit passes through it. If the resistance of the galvanometer is $G$,the shunt resistance $S$ connected to the galvanometer is

Two identical moving coil galvanometers have $10 \Omega$ resistance and full scale deflection at $2 \mu A$ current. One of them is converted into a voltmeter of $100 \text{ mV}$ full scale reading and the other into an ammeter of $1 \text{ mA}$ full scale current using appropriate resistors. These are then used to measure the voltage and current in the Ohm's law experiment with $R = 1000 \Omega$ resistor by using an ideal cell. Which of the following statement$(s)$ is/are correct?
$(1)$ The measured value of $R$ will be $980.2 \Omega$.
$(2)$ The resistance of the voltmeter will be $50 \text{ k} \Omega$.
$(3)$ The resistance of the ammeter will be $0.02 \Omega$ (rounded off to the $2^{\text{nd}}$ decimal place).
$(4)$ If the ideal cell is replaced by a cell having internal resistance of $5 \Omega$,then the measured value of $R$ will be more than $1000 \Omega$.