An electric bulb is designed to consume 55 W when operated at 110 volts. It is connected to a 220 V, 50 Hz line through a choke coil in series. What should be the inductance of the coil for which the bulb gets correct voltage?
Given: Power (P) = 55W,
Bulb operated at voltage (V) = 110V,
Voltage supplied (E) = 220V
Resistance (R) will be
Frequency (f) =50Hz,
Angular velocity 
will be
Current (I) in the circuit will be
Voltage drop across the resistor will be
Where, L is the inductance of the coil for which the bulb gets correct voltage.
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