AC Voltage Applied to a Series LCR Circuit

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AC Voltage Applied to a Series LCR Circuit: Overview

This topic covers concepts, such as, Total Impedance in Series L-C-R Circuit, Series LCR Circuit, Impedance Diagram for Series LCR Circuit & Voltage Versus ωt Graph for LCR Series Circuit etc.

Important Questions on AC Voltage Applied to a Series LCR Circuit

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An a.c. voltage of 100 V, 50 Hz is connected across 20 Ω resistor and 2 mH inductor in series. What is the impedance of the circuit?

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When an inductor L and a resistor R in series are connected across a 12 V, 50 Hz supply a current of 0.5 A flows in the circuit. The current differs in phase from applied voltage by  π3 radian. The value of R is 

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What is damped and undamped oscillation?

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In RLC circuits, the circuit oscillates if _____ is zero.

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In damped oscillation of LCR series circuit charge amplitude is expressed as ( where qm=charge amplitude at t=0)

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For small value of resistance damped oscillation of LCR circuit becomes as undamped LC oscillation in respect of angular frequency.

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According to voltage vs ωt graph in LCR series circuit, how phasor diagram will be represented.

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In LCR series circuit amplitude of voltage across inductor is ( if Peak value of current=I0 and inductive reactance=XL=ωL)

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When resistance R is connected in series with an element A, the electric current is found to be lagging behind the voltage V by angle 30°. When the same resistance is connected in series with element B, current leads by 60°. When R, AB are connected in series, the current now leads voltage by θ which is equal to tan-1K/3, then the value of K is (assume same AC source is used in all cases)

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In the series L-C-R circuit, the voltmeter and ammeter readings are respectively a V and b A. Find the value of a100+b.

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In AC series circuit, the resistance, inductive reactants and capacitive reactants are 3ohm, 10ohm and 14ohm respectivity. Find the impedance of the circuit.

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When 100 V DC is applied across a solenoid, a steady current of 1 A flows in it. When 100 V AC is applied across the same solenoid, the current drops to 0.5 A.If the frequency of the AC source is 1503/π Hz the impedance and inductance of the solenoid are :

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Assertion : In a series R, L, C circuit if VR, V1, and Vc denote r m s voltage across R, L and C respectively and Vs is the rms voltage across the source, then Vs=VR+VL+Vc.

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Reason:  Kirchoff voltage law is valid only for DC circuit, but it is not valid for AC circuit.

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What is the impedance of a series RLC circuit with resistance R=1354 Ω, capacitance C=2 μF and inductance L=2 H when the frequency of the source is 150 Hz. Round the answer to the nearest integer.

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In the figure shown the reading of voltmeters are V1=40 V, V2 =40 V and V3=10 V. Find the peak value of emf

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An AC source of angular frequency ω is fed across a resistor R and a capacitor C in series. The current registered is I. If now the frequency of source is changed to ω3 (but maintaining the same voltage), the current in the circuit is found to be halved. The ratio of reactance to resistance at the original frequency ω will be,

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A steady current of 2 A flows when an inductor of inductance 2mH is connected to ac source of emf 10 V. Now a capacitor of capacity 2μF is connected in series. If the current in the circuit is along the emf, the rms value of the current is

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For the ac circuit shown below, phase difference between emf and current is π4 radian as shown in the graph. If the impedance of the circuit is 1414 Ω then the values of P and Q are;

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In an LCR circuit, inductive reactance and capacitive reactance was found to be equal. The resistance was found to be 20 Ω. The probable impedance of the combination is

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In the given circuit, the reading of voltmeter VL and VC are 300 V each. The reading of the voltmeter VR and ammeter A are respectively,

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