Two electric bulbs, rated at $(25\, W, 220\, V)$ and $(100\, W, 220\, V)$, are connected in series acroos a $220\, V$ voltage source. If the $25\, W$ and $100\, W$ bulbs draw powers $P_1$ and $P_2$ respectively, then
$P_1 = 16\, W, P_2 = 4\, W$
$P_1 = 16\, W, P_2 = 9\, W$
$P_1 = 9\, W, P_2 = 16\, W$
$P_1 = 4\, W, P_2 = 16\, W$
An electric bulb is rated $220\, volt$ and $100\, watt$. Power consumed by it when operated on $110\, volt$ is ............. $watt$
A button battery is rated $3 \,V$ and $225 \,mAh . A$ cricket ball (mass $=0.163 \,kg$ ) having energy equal to that stored in the battety will have speed closest to ............ $\,m / s$
Two cities are $150\,\, km$ apart. Electric power is sent from one city to another city through copper wires. The fall of potential per $km$ is $8\,\, volt$ and the average resistance per km is $0.5 \,\,\Omega .$ The power loss in the wire is
If power in external resistance $R$ is maximum then
$(i) R = r$ $(ii)$ Power in $R$ is $\frac{{{E^2}}}{{4R}}$
$(iii)$ Input power $\frac{{{E^2}}}{{2R}}$ $(iv)$Efficiency is $50\%$
A heater draws a current of $2\,A$ when connected to a $250\,V$ source. The rate of energy dissipation is ............. $W$