An electric bulb marked as $50 W - 200 V$ is connected across a $100 V$ supply. The present power of the bulb is (in $W$)

Two electric bulbs have ratings $P_1 \text{ watt}, V \text{ volt}$ and $P_2 \text{ watt}, V \text{ volt}$. If they are connected in parallel to a $V \text{ volt}$ supply,the total power consumed will be:

Which device can convert all electrical energy into heat?

$A$ $220\, V$ and $800\, W$ electric kettle and three $220\, V$ and $100\, W$ bulbs are connected in parallel. On connecting this combination with a $220\, V$ electric supply,the total current will be ................ $A$.

$A$ rise of temperature of $4\,^oC$ is observed in a conductor by passing a current. If the current is tripled,the rise in temperature will be .............. $^oC$.

$A$ room heater is rated $400 \text{ W}$, $220 \text{ V}$. If the supply voltage drops to $200 \text{ V}$, what will be the power consumed (approximately) (in $\text{ W}$)?