Amount of electricity required to pass through the ${H_2O}$ voltmeter so as to liberate $11.2 \, L$ of hydrogen will be ............ $F$.

Assertion : All electric devices shown in the circuit are ideal. The reading of each of ammeter $(A)$ and voltmeter $(V)$ is zero.
Reason : An ideal voltmeter draws almost no current due to very large resistance, and hence $(V)$ and $(A)$ will read zero.

Two heaters $A$ and $B$ have power ratings of $1 \text{ kW}$ and $2 \text{ kW}$,respectively. These two are first connected in series and then in parallel to a fixed power source. The ratio of power outputs for these two cases is:

$A$ wire of length $L$ and $3$ identical cells of negligible internal resistances are connected in series. Due to current,the temperature of the wire is raised by $\Delta T$ in a time $t$. $A$ number $N$ of similar cells is now connected in series with a wire of the same material and cross-section but of length $2L$. The temperature of the wire is raised by the same amount $\Delta T$ in the same time $t$. The value of $N$ is

The supply voltage to a room is $120\ V$. The resistance of the lead wires is $6\,\Omega$. $A$ $60\ W$ bulb is already switched on. What is the decrease in voltage across the bulb when a $240\ W$ heater is switched on in parallel to the bulb? ............. $V$

Which of the following graphs represents the variation of power loss in the external load with external resistance $R$?