A heater draws a current of $2\,A$ when connected to a $250\,V$ source. The rate of energy dissipation is ............. $W$
$500$
$1000$
$250$
$125$
Thomson coefficient of a conductor is $10\,\mu V/K$. The two ends of it are kept at ${50\,^o}C$ and ${60\,^o}C$ respectively. Amount of heat absorbed by the conductor when a charge of $10\,C$ flows through it is
Two heaters $A$ and $B$ have power rating of $1 \mathrm{~kW}$ and $2 \mathrm{~kW}$, respectively. Those two are first connected in series and then in parallel to a fixed power source. The ratio of power outputs for these two cases is:
An electric bulb rated for $500\, watts$ at $100\, volts$ is used in a circuit having a $200-volt$ supply. The resistance $R$ that must be put in series with the bulb, so that the bulb draws $500\, W$ is .................. $\Omega$
The maximum power drawn out of the cell from a source is given by (where $r$ is internal resistance)
An electric lamp is marked $60\, W$, $230\, V$. The cost of a $1\, kWh$ of energy is Rs. $1.25$. The cost of using this lamp $8$ hrs a day for $30$ day is Rs. ...............