In the following circuit, bulb rated as $1.5\, V$, $0.45\, W$. If bulbs glows with full intensity then what will be the equivalent resistance between $X$ and $Y$ ............. $\Omega$
$0.45$
$1$
$3$
$5$
Two $220\; V , 100 \;W$ bulbs are connected first in series and then in parallel. Each time the combination is connected to a $220 \;V \;AC$ supply line. The power drawn by the combination in each case respectively will be
In the following circuit, $1 \,\Omega$ resistor dissipates power $P$. If the resistor is replaced by $9 \,\Omega$, the power dissipated in it is
A piece of fuse wire melts when a current of $15\, ampere$ flows through it. With this current, if it dissipates $22.5\, W$, the resistance of fuse wire will be .............. $\Omega$
A $220\, volt$, $1000\, W$ bulb is connected across a $110\, volt$ mains supply. The power consumed will be ............ $W$
$(a)$ Consider circuit in figure. How much energy is absorbed by electrons from the initial state of no current (ignore thermal motion) to the state of drift velocity ?
$(b)$ Electrons give up energy at the rate of $R{I^2}\;$ per second to the thermal energy. What time scale would number associate with energy in problem $(a)$ ? $n = no$ of electron/volume $ = {10^{29}}{m^{ - 3}}$, length of circuit $= 10$ $cm$, cross-section $=$ $A = $ ${\left( {1\,mm} \right)^2}$