An electric bulb is designed to consume 55W
Question:

An electric bulb is designed to consume $55 \mathrm{~W}$ when operated at 110 volts. It is connected to a $220 \mathrm{~V}$, $50 \mathrm{~Hz}$ line through a choke coil in series. What should be the coil for which the bulb gets correct voltage?

Solution: