An electric heater is marked with $220\, V$ and $1100\, W$. If it is used for $4\, hours$, the energy consumed in $kWh$ will be:

Two identical electric lamps marked $500\, W, 220\, V$ are connected in series and then joined to a $110\, V$ line. The power consumed by each lamp is

If voltage across a bulb rated $220 \,V, 100 \,W$ drops by $2.5 \%$ of its rated value, then the percentage of the rated value by which the power would decrease is (in $\%$)

What is the ratio of heat generated in resistors $R$ and $2R$ connected in parallel as shown in the figure?

How many calories of heat will be produced approximately in a $210\, W$ electric bulb in $5$ minutes?

$A$ bulb of $100 \text{ W}$ rating is connected with $220 \text{ V}$ supply. The resistance of the bulb is . . . . . . .