Q13 of 51 Page 330

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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11

A resistor of resistance 100 Ω is connected to an AC source ϵ = (12 V) sin (250 π s–1) t. Find the energy dissipated as heat during t = 0 to t = 1.0 ms.

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In a series RC circuit with an AC source R = 300Ω, C = 25 μF, ϵ0 = 50 V and v = 50/π Hz. Find the peak current and the average power dissipated in the circuit.

 14

In a series LCR circuit with an AC source, R = 300Ω, C = 20 μF, L = 1.0 Henry, ϵrms = 50 V and v = 50/π Hz. Find

(a) The rms current in the circuit and


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Consider the situation of the previous problem. Find the average electric field energy stored in the capacitor and the average magnetic field energy stored in the coil.