In an AC generator, a coil with N turns, all of the same area A and total resistance R, rotates with frequency ω in a magnetic field B. The maximum value of emf generated in […]
In a series resonant LCR circuit, the voltage across R is 100 volts and R =1kΩ with C= 2 μF. The resonant frequency ω is 200 rad/s. At resonance the voltage across L is
An LCR circuit contains resistance of 100 ohm and a supply of 200 volt at 300 radian angular frequency. If only capacitance is taken out from the circuit and the rest of the circuit is […]
An alternating voltage of 220 V, 50 Hz frequency is applied across a capacitor of capacitance 2 μF. The impedence of the circuit is
Options
(a) π/5000 (b) 1000/π (c) 500π (d) 5000/π
Correct […]
An inductor is connected to an a.c. source when compared to voltage, the current in the lead wires
Options
(a) is ahead in phase by π (b) lags in phase by π (c) […]
In a LCR series circuit, the potential difference between the terminals of the inductor is 60 V, between the terminals of the capacitor is 30 V and that across the resistance is 40 V. Then, […]
The rms current in an AC circuit is 2 A. If the wattless current be √3 A, what is the power factor of the circuit?
Options
(a) (1/2) (b) (1/3) (c) 1/√3 (d) 1/√2
Eddy currents are used in
Options
(a) Induction furnace (b) Electromagnetic breaks (c) Speedometers (d) All of these
Correct Answer:
Induction furnace
Explanation:
No explanation available. Be the first to write the explanation […]
The wing span of an aeroplane is 20 m. It is flying in a field where the vertical component of magnetic field of earth is 5×10⁻⁵ tesla with velocity 360 km/hour. The potential difference produced […]
An electric motor runs on DC source of emf 200 V and draws a current of 10 A. If the efficiency be 40%, then the resistance of armature is
Options
(a) 2Ω (b) […]
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