The reading of the voltmeter in the circuit shown is ............. $V$. (in $.25$)

Water boils in an electric kettle in $15\,\text{min}$ after switching on. If the length of the heating wire is decreased to $2/3$ of its initial value,then the same amount of water will boil with the same supply voltage in ............. $\text{min}$.

To verify Ohm's law,a student connects the voltmeter across the battery as shown in the figure. The measured voltage is plotted as a function of the current,and the following graph is obtained. If $V_0$ is almost zero,identify the correct statement.

The equivalent resistance between the points $A$ and $B$ in the following infinite circuit is (in $Omega$)

Two bulbs of equal wattage,one having a carbon filament and the other having a tungsten filament,are connected in series to the mains. Then:

An ammeter and a voltmeter of resistance $R$ are connected in series to an electric cell of negligible internal resistance. Their readings are $A$ and $V$ respectively. If another resistance $R$ is connected in parallel with the voltmeter, what happens to the readings $A$ and $V$?