Two wires $A$ and $B$ of same material and mass have their lengths in the ratio $1 : 2$. On connecting them to the same source, the rate of heat dissipation in $B$ is found to be $5\,W$. The rate of heat dissipation in $A$ is............ $W$
$10$
$5$
$20$
None of these
If a power of $100\, W$ is being supplied across a potential difference of $200\, V$, current flowing is ............ $A$
The two bulbs as in the above question are connected in series to a $200\, volt$ line. Then
Following figures show different combinations of identical bulb$(s)$ connected to identical battery$(ies)$. Which option is correct regarding the total power dissipated in the circuit?
In the circuit shown in figure, the heat produced in $5\, ohm $ resistance is $10\, cal / sec$ . The heat produced in $4$ resistance is ................ $cal /sec$
If voltage across a bulb rated $220$ $volt-$ $100$ $watt$ drops by $2.5\%$ of its rated value, the percentage of the rated value by which the power would decrease is ............... $\%$