In an electric heater $4\, amp$ current passes for $1$ minute at potential difference of $250\, volt$, the power of heater and energy consumed will be respectively
$1\, kW$, $60\, kJ$
$0.5\, kW$, $30\, kJ$
$10\, kW$, $600\, kJ$
None of these
Three resistors of $4\,\Omega ,6\,\Omega $ and $12\,\Omega $ are connected in parallel and the combination is connected in series with a $1.5\, V$ battery of $1\,\Omega $ internal resistance. The rate of Joule heating in the $4\,\Omega $ resistor is ................ $W$
The value of the resistance $R$ in figure is adjusted such that power dissipated in the $2\,\Omega$ resistor is maximum. Under this condition
Three electric bulbs of $200\,W,\,\,200\,W$ and $400\,W$ are shown in figure. The resultant power of the combination is ................ $W$
Three equal resistors connected in series across a source of $e.m.f.$ together dissipate $10\, watt$. If the same resistors are connected in parallel across the same $e.m.f.$, then the power dissipated will be .............. $watt$
The internal resistance of a primary cell is $4\, ohm$. It generates a current of $0.2\, amp$ in an external resistance of $21\, ohm$. The rate at which chemical energy is consumed in providing the current is .............. $J/s$