A battery is charged at a potential of $15\, V$ for $8$ hours when the current flowing is $10\, A$. The battery on discharge supplies a current of $5\, A$ for $15$ hours. The mean terminal voltage during discharge is $14\, V$. The "Watt-hour" efficiency of the battery is .............. $\%$
$82.5$
$80$
$90$
$87.5$
In the figure shown the power generated in $y$ is maximum when $y = 5\,\Omega $. Then $R$ is
Two resistances ${R_1}$ and ${R_2}$ when connected in series and parallel with $120\, V$ line, power consumed will be $25\, W$ and $100\, W$ respectively. Then the ratio of power consumed by ${R_1}$ to that consumed by ${R_2}$ will be
The maximum power delivered to resistance $R$ is ............... $W$
Two bulbs are working in parallel order. Bulb $A$ is brighter than bulb $B$. If ${R_A}$ and ${R_B}$ are their resistance respectively then
Two identical heater filaments are connected first in parallel and then in series. At the same applied voltage, the ratio of heat produced in same time for parallel to series will be: