$A$ galvanometer of resistance $G$ has a voltage range $V_g$. The resistance required to convert it to read voltage up to $V$ is

$A$ rectangular coil of effective area $0.05 \ m^2$ is suspended freely in a radial magnetic field of $0.01 \ Wb/m^2$. The torsional constant of the suspension fiber is $5 \times 10^{-9} \ Nm/\text{degree}$. If a current of $300 \ \mu A$ is passed through it,then the angle through which the coil rotates is (in $^{\circ}$)

$A$ multirange voltmeter can be constructed by using a galvanometer circuit as shown in the figure. We want to construct a voltmeter that can measure $2 \ V$,$20 \ V$,and $200 \ V$ using a galvanometer of resistance $10 \ \Omega$ that produces maximum deflection for a current of $1 \ mA$. Find $R_1$,$R_2$,and $R_3$ that have to be used.

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 $1000 \Omega$.

To make the magnetic field radial in a moving coil galvanometer:

$A$ galvanometer gives a full-scale reading of $50 \ mA$,when a potential difference across its terminals is $0.15 \ V$. It can be used as an ammeter of range $0 - 100 \ A$ by connecting a shunt resistance of: (in $\Omega$)