On giving $220\,V$ to a resistor the power dissipated is $40\,W$ then value of resistance is ............... $\Omega$
$1210$
$2000$
$1000$
None of these
If a high power heater is connected to electric mains, then the bulbs in the house become dim, because there is a
An electric bulb of $500 \,watt$ at $100\, volt$ is used in a circuit having a $200\, {V}$ supply. Calculate the resistance ${R}$ to be connected in series with the bulb so that the power delivered by the bulb is $500\, {W}$. (in $\Omega$)
Two resistors of resistance, $100\,\Omega$ and $200\,\Omega$ are connected in parallel in an electrical circuit. The ratio of the thermal energy developed in $100\,\Omega$ to that in $200\,\Omega$ in a given time is:
The energy consumed in $1\, Kwatt$ electric heater in $30$ seconds will be
A $100\, watt$ bulb working on $200 \,volt$ and a $200\, watt$ bulb working on $100\, volt$ have