The figure shows a network of four resistances and three batteries The electrical power dissipated as heat is .............. $W$

What will happen when a $40\, watt$, $220\, volt$ lamp and $100\, watt$, $220\, volt$ lamp are connected in series across $40\, volt$ supply

In the circuit shown, the resistance $r$ is a variable resistance. If for $r = fR,$  the heat generation in $r$ is maximum then the value of $f$ is 

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

Two heaters $A$ and $B$ have power rating of $1 \mathrm{~kW}$ and $2 \mathrm{~kW}$, respectively. Those 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:

In the figure shown the power generated in $y$ is maximum when $y = 5\,\Omega $. Then $R$ is