EASY
Earn 100

Why is it called a rejector circuit?

 

Important Questions on Alternating Current

MEDIUM
For an RLC circuit driven with voltage of amplitude vm and frequency ω0=1LC the current exhibits resonance. The quality factor, Q is given by
EASY
A series combination of resistor of resistance 100 Ω inductor of inductance 1 H and capacitor of capacitance 6.25 μF is connected to an ac source. The quality factor of the circuit will be _____.
EASY

The readings of ammeter and voltmeter in the following circuit are respectively

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EASY
An alternating current is flowing through a series L-C-R circuit. It is found that the current reaches a value of 1 mA at both 200 Hz and 800 Hz frequency. What is the resonance frequency of the circuit?
HARD

The amplitude of the current in series LCR circuit connected to an AC frequency "ω"is given by,

im=vmR2+XL-XC2.

Where  XL and XC are inductive and capacitive reactants respectively and "vm" is the amplitude of the voltage. Starting from this equation show that the sharpness of resonance the circuit is equal to the quality factorof the circuit.

EASY

In the given circuit, the resonant frequency is

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MEDIUM

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In the above circuit, C= 3 2 μF, R 2 =20 Ω,L= 3 10 H and R 1 =10 Ω. Current in L-R1 path is I1 and in C-R2 path it is I 2 . The voltage of AC source is given by, V=200 2 sin( 100t ) volts. The phase difference between I1 and I2 is:

EASY
An LCR series circuit has an inductance of 100 mH, connected to a 100 μF capacitor and the resistive load is 120 Ω, which is connected to an A.C. source of 60 Hz. The resonant frequency of the circuit is:
EASY
For L-C-R ac circuit resonance frequency is 500 Hz and the frequency at half power points  are 450 Hz  and 550 Hz. What will be Q factor?
MEDIUM

A series LCR circuit contains a pure inductor of inductance 5.0 H, a capacitor of capacitance 20 μF and a resistor of 40 Ω. Calculate the Quality factor (Q-factor) of the circuit. 

MEDIUM

A parallel plate capacitor in series with a resistance of 100 Ω, an inductor of 20 mH and an AC voltage source of variable frequency shows resonance at a frequency of 1250πHz. If this capacitor is charged by a DC voltage source to a voltage 25 V, what amount of charge will be stored in each plate of the capacitor?

EASY
In a series LCR resonant circuit, the quality factor is measured as 100. If the inductance is increased by two fold and resistance is decreased by two fold, then the quality factor after this change will be _______
MEDIUM

Find the peak current and resonant frequency of the following circuit (as shown in figure).

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MEDIUM
 A resonant AC circuit contains a capacitor of capacitance 10-6 F and an inductor of 10-4 H. The frequency of electrical oscillations will be :- 
MEDIUM
A transmitting station releases waves of wavelength 960 m. A capacitor of 2.56 μF is used in the resonant circuit. The self-inductance of coil necessary for resonance is x×10-8 H. Find x
EASY
In an LCR series circuit (of inductance L, capacitance C and resistance R), the impedance is minimum when the angular frequency of the source is given by
EASY
A resistance of 10 Ω is joined to an inductance of 0.5 H and a capacitance of 20.24×10-6 F. When the circuit is connected to the mains supply of 200 V and frequency 50 cycle per second, maximum current flows in the circuit. The value of current is
EASY
For a series LCR circuit with L=2 H, C=18 μF and R=10 Ω. What is the value Q-factor of this circuit?
EASY
The Q factor for a damped oscillator is given by the
EASY
A resonance circuit having inductance and resistance 2×10-4 H and 6.28 Ω respectively oscillates at 10 MHz frequency. The value of quality factor of this resonator is_______. π=3.14