A $60\, watt$ bulb carries a current of $0.5\, amp$. The total charge passing through it in $1$ hour is ............ $coulomb$
$3600$
$3000$
$2400 $
$1800$
A bulb rated at ($100\,W$ - $200\,V$) is used on a $100\,V$ line. The current in the bulb is
The temperature at which thermal electric power of a thermo couple becomes zero is called
Which device can convert all electrical energy into heat
A capacitor of capacitance $5\,\mu F$ is connected to a source of constant $emf$ of $200\,V$ for a long time, then the switch was shifted to contact $2$ from contact $1$ . The total amount of heat generated in the $500\,\Omega $ resistance, thereafter is
A heater coil connected to a supply of a $220\, V$ is dissipating some power ${P_1}.$ The coil is cut into half and the two halves are connected in parallel. The heater now dissipates a power ${P_2}.$ The ratio of power ${P_1}\,\,:\,\,{P_2}$ is