An ammeter of resistance $20 \Omega$ gives full scale deflection when $1 \text{ mA}$ current flows through it. What is the maximum current that can be measured by connecting $4$ resistors each of $16 \Omega$ in parallel with the meter (in $\text{ mA}$)?

The current sensitivity of a moving coil galvanometer is increased by $25 \%$. This increase is achieved only by changing the number of turns of the coils and the area of the cross-section of the wire while keeping the resistance of the galvanometer coil constant. The percentage change in the voltage sensitivity will be $...........\%$

To convert a galvanometer into an ammeter,one needs to connect a

$A$ galvanometer of resistance $G$ is shunted by a resistance of $5 \Omega$. To keep the main current in the circuit unchanged,the resistance to be put in series with the same galvanometer is

$A$ voltmeter has a resistance of $G \, \Omega$ and a range of $V \, \text{volts}$. The value of the resistance that must be connected in series to convert it into a voltmeter of range $nV \, \text{volts}$ is:

$A$ milliammeter of range $10\, mA$ and resistance $9\, \Omega$ is joined in a circuit as shown. The meter gives full-scale deflection for current $I$ when $A$ and $B$ are used as its terminals,i.e.,current enters at $A$ and leaves at $B$ ($C$ is left isolated). The value of $I$ is