Two identical heaters rated $220\, volt$, $1000\, watt$ are placed in series with each other across $220 \,volt$ lines. If resistance do not change with temperature, then the combined power is ............. $watt$

A heating coil is labelled $100\, W$, $220\, V$. The coil is cut in half and the two pieces are joined in parallel to the same source. The energy now liberated per second is .............. $J$

A $6.0\,volt$ battery is connected to two light bulbs as shown in figure. Light bulb $1$ has resistance $3\,ohm$ while light bulb $2$ has resistance $6\,ohm.$ Battery has negligible internal resistance. Which bulb will glow brighter?

The resistance of the filament of a lamp increases with the increase in temperature. A lamp rated $100\, W, 220\, V$ is connected across $220\, V$ power supply. If the voltage drops by $10\%$ then the power of lamp will be

The capacitor $C$ is initially without charge.$X$ is now j oined to $Y$ for a long time, during which $H_1$ heat is produced in the resistance $R$. $X-Y$ connection is removed and $X$ is now joined to $Z$ for a long time, during which heat $H_2$ is produced in $R$.

Two electric bulbs whose resistances are in the ratio of $1 : 2$ are connected in parallel to a constant voltage source. The powers dissipated in them have the ratio