LCR Series Circuit

Author:Embibe Experts
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Important Questions on LCR Series Circuit

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A coil of resistance 200 ohms and self-inductance 1.0 H has been connected to an A.C. source of frequency 200π Hz. The phase difference between voltage and current is 

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The equation of alternating current is, i=502sin400πt A. Then, the frequency and root-mean-square value of current are, respectively,

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An alternating voltage E(in volt)=2002sin100t is connected to a 1 μF capacitor through an AC ammeter. The reading of the ammeter shall be,

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A coil having an inductance of 1π henry is connected in series with a resistance of 300 Ω. If 20 volts from a 200 cycle source is impressed across the combination, the value of the phase angle between the voltage and the current is,

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In an LR circuit, the value of L is 0.4π henry and the value of R is 30 ohm. If in the circuit, an alternating emf of 200 volts at 50 cycles per second is connected, the impedance of the circuit and current will be,

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In the alternating current shown in the following figure, the currents through inductor and capacitor ar 1.2 amp and 1.0 amp, respectively. The current drawn from the generator is 

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A circuit has a self-inductance of 1 H and carries a current of 2 A. To prevent sparking, when the circuit is switched off, a capacitor which can withstand 400 V is used. The least capacitance of capacitor connected across the switch must be equal to,

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In a series LCR circuit, C=25 μF, L=0.1 H and R=25 Ω. The emf of the A.C. source is e=311sin314t volt, then the impedance is,

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An inductive circuit contains a resistance of 10 Ω and an inductance of 2.0 H. If an AC voltage of 120 V and frequency of 60 Hz is applied to this circuit, the current in the circuit would be nearly,

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A sinusoidal voltage V0sinωt is applied across a series combination of resistance R and capacitance C. The amplitude of the current in this circuit is,

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Resonance frequency of a circuit is f. If the capacitance is made 4 times the initial value, then the resonance frequency will become:

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A 10 Ω resistance, 5 mH coil and 10 μF capacitor are joined in series. When a variable frequency alternating current source is joined to this combination, the circuit resonates. If the resistance is halved, the resonance frequency:

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An A.C. source is in series with R and L. If respective potential drops are 200 V and 150 V, what is the applied voltage ?

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An inductor 20×10-3 H , a capacitor 100 μF, and a resistor 50 Ω are connected in series across a source of emfV=10sin314t. If resistance is removed from the circuit and the value of inductance is doubled, then the variation of current with time in the new circuit is

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An alternating emf 10cos100t volt is connected in series with a resistance of 10 ohm and inductance of 100 mH. What is the phase difference?

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In a LR circuit the A.C. source has voltage 220 V and the potential difference across the inductance is 176 V. The potential difference across the resistance will be:

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The current in an L-R circuit builds up to 34th of its steady state value in 4 seconds. The time constant of this circuit is

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An LCR circuit contains R=50 Ω, L=1 mH and C=0.1 μF. The impedance of the circuit will be minimum for a frequency of: