RC, LR and LC Circuits with AC Sources

IMPORTANT

RC, LR and LC Circuits with AC Sources: Overview

This topic covers concepts, such as Capacitive Reactance, Choke Coil, Instantaneous Power in R-C Series AC Circuit, Pure Capacitance AC Circuit, Total Impedance in Series L-C-R Circuit, Special Cases in Series LCR Circuit, etc.

Important Questions on RC, LR and LC Circuits with AC Sources

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An a.c. source, of voltage V=Vm sin ωt, is applied across a series LCR circuit. Which of the following is the phasor diagram for the circuit when capacitative impedance exceeds the inductive impedance?

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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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Graph showing variation of current with frequency of AC source in a series LCR circuit is,

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Consider the circuit shown below. The input to the circuit is Vin =10cos(1000t). The values of the components are R=1  and C=1 μF respectively. Then the R.M.S. value of the current flowing in the circuit is,

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If the current in inductance is 0.8 A and that in capacitance is 0.6 A. What is the current drawn from the source?

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How do you find total impedance in a series parallel circuit?

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How do you draw a phasor diagram for RC circuit?

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What is the formula for impedance in an RL series circuit?

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What is the impedance of LR series circuit?

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What is average power in AC circuit derive an expression to obtain average power

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What is the power consumed in RC circuit?

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What is the formula for power in AC RC series circuit?

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What is the impedance of LR series circuit?

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How do you find the impedance of an ac circuit?

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What is the power consumed in RC circuit?

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What is a RC circuit in physics?

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The average power dissipated in a pure inductance is

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Assertion : The alternating current lags behind the e.m.f. by a phase angle of π2, when AC flows through an inductor.
Reason : The inductive reactance increases as the frequency of AC source decreases.