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Series Parallel Resonance Questions and Answers for Viva
Series Parallel Resonance Viva Questions and Answers
Frequently asked questions and answers of Series Parallel Resonance in Electronics Devices and Circuits of Electronics Engineering to enhance your skills, knowledge on the selected topic. We have compiled the best Series Parallel Resonance Interview question and answer, trivia quiz, mcq questions, viva question, quizzes to prepare. Download Series Parallel Resonance FAQs in PDF form online for academic course, jobs preparations and for certification exams .
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Interview Question and Answer of Series Parallel Resonance
Question-1. What is meant by electrical resonance?
Answer-1: When impedance in the circuit is minimum current is maximum this is known as electrical resonance.
Question-2. What is the condition for resonance?
Answer-2: X L = X C Inductive reactance = capacitive reactance, Z becomes minimum, When Z = R.
Question-3. What is the value of Z in LCR series circuit at resonance?
Answer-3: Z = R
Question-4. What is the resonance frequency?
Answer-4: The frequency of applied AC at which resonance takes place or current is maximum.
Question-5. Expression for resonance frequency?
Answer-5: f o = 1 / 2πsqrt(LC) , f o is independent of circuit resistance.
Question-6. Define band width ?
Answer-6: In series LCR circuit, bandwidth is defined as the range of frequency for which the power dissipated in the resistance is equal to half the power dissipated at resonance.
Question-7. In general, what is the expression for bandwidth ?
Answer-7: Bandwidth=(f 2 - f 1 ) in Hz
Question-8. What are f 1 , f 2 ?
Answer-8: f 1 , f 2 are half power frequencies. The values of frequencies at which the power input is half its maximum value are called half power frequencies.
Question-9. What are characteristics of series resonance?
Answer-9: a) Z is minimum when Z = R. b) I is maximum, I m = V / Z min = V / R c) I is in phase with V i.e. φ = 0. d) Reactance = 0, i.e. X L = X C .
Question-10. Why do you call LCR series resonance circuit as an acceptor circuit?
Answer-10: It offers a low impedance to the current at a resonance frequency, it is called acceptor circuit
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To Study the Condition of Resonance for a Series LCR Circuit
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Microwave Engineering Questions and Answers – Series and Parallel Resonant Circuits
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- Resonance in Series-Parallel Circuits
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In simple reactive circuits with little or no resistance, the effects of radically altered impedance will manifest at the resonance frequency predicted by the equation given earlier. In a parallel (tank) LC circuit, this means infinite impedance at resonance. In a series LC circuit, it means zero impedance at resonance:
![lcr series and parallel resonance experiment viva questions lcr series and parallel resonance experiment viva questions](https://www.allaboutcircuits.com/uploads/articles/impedance-resonance-formula.jpg)
However, as soon as significant levels of resistance are introduced into most LC circuits, this simple calculation for resonance becomes invalid.
On this page, we’ll take a look at several LC circuits with added resistance , using the same values for capacitance and inductance as before: 10 µF and 100 mH, respectively.
Calculating the Resonant Frequency of a High-Resistance Circuit
According to our simple equation above, the resonant frequency should be 159.155 Hz. Watch, though, where current reaches maximum or minimum in the following SPICE analyses:
![lcr series and parallel resonance experiment viva questions Parallel LC circuit with resistance in series with L.](https://www.allaboutcircuits.com/uploads/articles/parallel-lc-circuit-with-resistance.jpg)
Parallel LC circuit with resistance in series with L.
![lcr series and parallel resonance experiment viva questions Resistance in series with L produces minimum current at 136.8 Hz instead of calculated 159.2 Hz](https://www.allaboutcircuits.com/uploads/articles/parallel-lc-circuit-with-resistance-result.jpg)
Resistance in series with L produces minimum current at 136.8 Hz instead of calculated 159.2 Hz
![lcr series and parallel resonance experiment viva questions Parallel LC with resistance in serieis with C.](https://www.allaboutcircuits.com/uploads/articles/parallel-lc-with-resistance-in-serieis.jpg)
Parallel LC with resistance in serieis with C.
Here, an extra resistor (Rbogus) is necessary to prevent SPICE from encountering trouble in analysis. SPICE can’t handle an inductor connected directly in parallel with any voltage source or any other inductor, so the addition of a series resistor is necessary to “break up” the voltage source/inductor loop that would otherwise be formed.
This resistor is chosen to be a very low value for minimum impact on the circuit’s behavior.
![lcr series and parallel resonance experiment viva questions Resistance in series with C shifts minimum current from calculated 159.2 Hz to roughly 180 Hz.](https://www.allaboutcircuits.com/uploads/articles/resistance-in-series-with-c-shifts.jpg)
Resistance in series with C shifts minimum current from calculated 159.2 Hz to roughly 180 Hz.
Series LC Circuits
Switching our attention to series LC circuits, we experiment with placing significant resistances in parallel with either L or C. In the following series circuit examples, a 1 Ω resistor (R1) is placed in series with the inductor and capacitor to limit total current at resonance.
The “extra” resistance inserted to influence resonant frequency effects is the 100 Ω resistor, R2. The results are shown in the figure below.
![lcr series and parallel resonance experiment viva questions Series LC resonant circuit with resistance in parallel with L.](https://www.allaboutcircuits.com/uploads/articles/series-lc-resonant-circuit-with-resistance-in-parallel-with-l.jpg)
Series LC resonant circuit with resistance in parallel with L.
![lcr series and parallel resonance experiment viva questions Series resonant circuit with resistance in parallel with L shifts maximum current from 159.2 Hz to roughly 180 Hz.](https://www.allaboutcircuits.com/uploads/articles/series-lc-resonant-circuit-with-resistance-in-parallel-with-l-results.jpg)
Series resonant circuit with resistance in parallel with L shifts maximum current from 159.2 Hz to roughly 180 Hz.
And finally, a series LC circuit with the significant resistance in parallel with the capacitor The shifted resonance is shown below.
![lcr series and parallel resonance experiment viva questions Series LC resonant circuit with resistance in parallel with C.](https://www.allaboutcircuits.com/uploads/articles/series-lc-resonant-circuit-with-resistance-in-parallel-with-c.jpg)
Series LC resonant circuit with resistance in parallel with C.
![lcr series and parallel resonance experiment viva questions Resistance in parallel with C in series resonant circuit shifts current maximum from calculated 159.2 Hz to about 136.8 Hz.](https://www.allaboutcircuits.com/uploads/articles/series-lc-resonant-circuit-with-resistance-in-parallel-with-c-results.jpg)
Resistance in parallel with C in series resonant circuit shifts current maximum from calculated 159.2 Hz to about 136.8 Hz.
Antiresonance in LC Circuits
The tendency for added resistance to skew the point at which impedance reaches a maximum or minimum in an LC circuit is called antiresonance . The astute observer will notice a pattern between the four SPICE examples given above, in terms of how resistance affects the resonant peak of a circuit:
Parallel (“tank”) LC circuit:
- R in series with L: resonant frequency shifted down
- R in series with C: resonant frequency shifted up
Series LC circuit:
- R in parallel with L: resonant frequency shifted up
- R in parallel with C: resonant frequency shifted down
Again, this illustrates the complementary nature of capacitors and inductors : how resistance in series with one creates an antiresonance effect equivalent to resistance in parallel with the other. If you look even closer to the four SPICE examples given, you’ll see that the frequencies are shifted by the same amount , and that the shape of the complementary graphs are mirror-images of each other!
Antiresonance is an effect that resonant circuit designers must be aware of. The equations for determining antiresonance “shift” are complex, and will not be covered in this brief lesson. It should suffice the beginning student of electronics to understand that the effect exists, and what its general tendencies are.
The Skin Effect
Added resistance in an LC circuit is no academic matter. While it is possible to manufacture capacitors with negligible unwanted resistances, inductors are typically plagued with substantial amounts of resistance due to the long lengths of wire used in their construction.
What is more, the resistance of wire tends to increase as frequency goes up, due to a strange phenomenon known as the skin effect where AC current tends to be excluded from travel through the very center of a wire, thereby reducing the wire’s effective cross-sectional area.
Thus, inductors not only have resistance, but changing, frequency-dependent resistance at that.
Added Resistance in Circuits
As if the resistance of an inductor’s wire weren’t enough to cause problems, we also have to contend with the “core losses” of iron-core inductors, which manifest themselves as added resistance in the circuit.
Since iron is a conductor of electricity as well as a conductor of magnetic flux, changing flux produced by alternating current through the coil will tend to induce electric currents in the core itself ( eddy currents ).
This effect can be thought of as though the iron core of the transformer were a sort of secondary transformer coil powering a resistive load: the less-than-perfect conductivity of the iron metal. This effects can be minimized with laminated cores, good core design high-grade materials, but never completely eliminated.
RLC Circuits
One notable exception to the rule of circuit resistance causing a resonant frequency shift is the case of series resistor-inductor-capacitor (“RLC”) circuits. So long as all components are connected in series with each other, the resonant frequency of the circuit will be unaffected by the resistance. The resulting plot is shown below.
![lcr series and parallel resonance experiment viva questions Series LC with resistance in series.](https://www.allaboutcircuits.com/uploads/articles/series-lc-with-resistance-in-series.jpg)
Series LC with resistance in series.
![lcr series and parallel resonance experiment viva questions Resistance in series resonant circuit leaves current maximum at calculated 159.2 Hz, broadening the curve.](https://www.allaboutcircuits.com/uploads/articles/series-lc-with-resistance-in-series-result.jpg)
Resistance in series resonant circuit leaves current maximum at calculated 159.2 Hz, broadening the curve.
Note that the peak of the current graph has not changed from the earlier series LC circuit (the one with the 1 Ω token resistance in it), even though the resistance is now 100 times greater. The only thing that has changed is the “sharpness” of the curve.
Obviously, this circuit does not resonate as strongly as one with less series resistance (it is said to be “less selective”), but at least it has the same natural frequency!
Antiresonance’s Dampening Effect
It is noteworthy that antiresonance has the effect of dampening the oscillations of free-running LC circuits such as tank circuits. In the beginning of this chapter we saw how a capacitor and inductor connected directly together would act something like a pendulum, exchanging voltage and current peaks just like a pendulum exchanges kinetic and potential energy.
In a perfect tank circuit (no resistance), this oscillation would continue forever, just as a frictionless pendulum would continue to swing at its resonant frequency forever. But frictionless machines are difficult to find in the real world, and so are lossless tank circuits.
Energy lost through resistance (or inductor core losses or radiated electromagnetic waves or . . .) in a tank circuit will cause the oscillations to decay in amplitude until they are no more. If enough energy losses are present in a tank circuit, it will fail to resonate at all.
Antiresonance’s dampening effect is more than just a curiosity: it can be used quite effectively to eliminate unwanted oscillations in circuits containing stray inductances and/or capacitances, as almost all circuits do. Take note of the following L/R time delay circuit: (Figure below)
![lcr series and parallel resonance experiment viva questions L/R time delay circuit](https://www.allaboutcircuits.com/uploads/articles/lr-time-delay-circuit.jpg)
L/R time delay circuit
The idea of this circuit is simple: to “charge” the inductor when the switch is closed. The rate of inductor charging will be set by the ratio L/R, which is the time constant of the circuit in seconds.
However, if you were to build such a circuit, you might find unexpected oscillations (AC) of voltage across the inductor when the switch is closed. (Figure below) Why is this? There’s no capacitor in the circuit, so how can we have resonant oscillation with just an inductor, resistor, and battery?
![lcr series and parallel resonance experiment viva questions Inductor ringing due to resonance with stray capacitance.](https://www.allaboutcircuits.com/uploads/articles/inductor-ringing-due-to-resonance.jpg)
Inductor ringing due to resonance with stray capacitance.
All inductors contain a certain amount of stray capacitance due to turn-to-turn and turn-to-core insulation gaps. Also, the placement of circuit conductors may create stray capacitance. While clean circuit layout is important in eliminating much of this stray capacitance, there will always be some that you cannot eliminate.
If this causes resonant problems (unwanted AC oscillations), added resistance may be a way to combat it. If resistor R is large enough, it will cause a condition of antiresonance, dissipating enough energy to prohibit the inductance and stray capacitance from sustaining oscillations for very long.
Interestingly enough, the principle of employing resistance to eliminate unwanted resonance is one frequently used in the design of mechanical systems, where any moving object with mass is a potential resonator.
A very common application of this is the use of shock absorbers in automobiles. Without shock absorbers, cars would bounce wildly at their resonant frequency after hitting any bump in the road. The shock absorber’s job is to introduce a strong antiresonant effect by dissipating energy hydraulically (in the same way that a resistor dissipates energy electrically).
- Added resistance to an LC circuit can cause a condition known as antiresonance , where the peak impedance effects happen at frequencies other than that which gives equal capacitive and inductive reactances.
- Resistance inherent in real-world inductors can contribute greatly to conditions of antiresonance. One source of such resistance is the skin effect , caused by the exclusion of AC current from the center of conductors. Another source is that of core losses in iron-core inductors.
- In a simple series LC circuit containing resistance (an “RLC” circuit), resistance does not produce antiresonance. Resonance still occurs when capacitive and inductive reactances are equal.
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Series LCR Circuits
In contrast to direct current (DC), which travels solely in one direction, Alternating Current (AC) is an electric current that occasionally reverses direction and alters its magnitude constantly over time. Alternating current is the type of electricity that is delivered to companies and homes, and it is the type of electricity that is used by consumers when they plug in kitchen appliances, televisions, fans, and electric lamps to a wall outlet. A flashlight’s battery cell is a frequent source of DC power. When modifying current or voltage, the abbreviations AC and DC are frequently used to signify merely alternating and direct.
In most electric power circuits, the most common waveform of alternating current is a sine wave, whose positive half-period correlates to the positive current direction and vice versa. The current may not truly reverse direction (as for the labeled pulsating waveform). Different waveforms, such as triangle waves or square waves, are employed in various applications, such as guitar amplifiers. Alternating current also includes audio and radio signals transmitted by electrical lines. Information like sound (audio) or images (video) is occasionally transmitted via modulation of an AC carrier signal in these forms of alternating current. The frequency of these currents is usually higher than that of power transmission currents.
Series LCR Circuit
An LCR circuit is made up of three components: an inductor (L), a capacitor (C), and a resistor (R). A tuned or resonant circuit is another name for it. A series LCR circuit is made up of these devices that are connected in series. As a result, the resistor, capacitor, and inductor will all have the same amount of current flowing through them.
A voltage V S is applied across the LCR series circuit in the above circuit, which depicts a simple LCR series circuit. Impedance is the amount of resistance a circuit provides to current flow. It’s the effective resistance to alternating current flow in an electric circuit made up of numerous electric components. It is caused by the interaction of ohmic resistance, capacitive reactance, and inductive reactance. If R denotes resistance, X L denotes inductive reactance, X C denotes capacitive reactance, then Z denotes impedance.
Z=√ R 2 +(X C −X L ) 2
Derivation for AC Voltage applied across Series LCR Circuit
![lcr series and parallel resonance experiment viva questions lcr series and parallel resonance experiment viva questions](https://media.geeksforgeeks.org/wp-content/uploads/20220417172901/LCRcircuit.jpg)
An inductor (L), capacitor (C), and resistor (R) are linked in series in the electrical circuit, which is powered by an AC voltage supply. The alternating voltage V is supplied by the voltage source, where
V=V m sin(ωt) where, V m is the amplitude of the applied voltage, and ω is the frequency of the applied voltage.
If q is the charge on the capacitor and I is the current flowing in the circuit at any moment t, the voltage equation for the circuit can be written as follows:
Net EMF across the circuit: V (source voltage) = Voltage drop across resistor + Voltage drop across capacitor + Self-induced Faraday’s emf in the inductor
V=L(di/dt) + IR + q/C
The inductor’s self-inductance is denoted by L.
Substituting alternating voltage for the expression,
V m sin(ωt) = L(di/dt) + IR + q/C …..(1)
Let us use the analytical method to determine the instantaneous current I or its matching phase to the applied alternating voltage V. We know that current is equal to the rate at which electric charge flows per unit of time, i.e.,
Differentiating both sides with respect to time, we get:
dI/dt=d 2 q/dt 2
The voltage equation in terms of q is obtained by substituting the above value into equation (1):
V m sin(ωt) = L(d 2 q/dt 2 ) + (dq/dt)R + q/C ……(2)
The equation for a forced or damped harmonic oscillator is similar to this equation.
q = q m sin(ωt+θ)
Differentiating both sides with respect to time,
dq/dt = q m ωcos(ωt+θ)
d 2 q/dt 2 =–q m ω 2 sin(ωt+θ)
Substituting these values in equation (2),
V m sin(ωt) = q m ω [Rcos(ωt+θ) + (X C –X L )sin(ωt+θ)] …..(3)
Here, Capacitive reactance: X C =1/ωC Inductive reactance: X L =ωL Impedance: Z= √R2+(X C −X L ) 2
Substituting the above values in equation (3), so we get:
V m sin(ωt)=q m ωZ[R/Z cos(ωt+θ) + (X C –X L )/Zsin(ωt+θ)] ……(4)
(X C –X L )/Z = sin∅
Dividing the two equations:
(X C –X L )/R=tan∅
∅=tan –1 ((X C –X L )/R)
Substituting the above values in equation (4):
V m sin(ωt)=q m ωZ[cos(ωt+θ–∅)]
Comparing the LHS and RHS of this equation, we get
V m =q m ωZ=I m Z
The current in the LCR circuit,
I = q m ωcos(ωt+θ)
I = I m cos(ωt+θ) [where, q m ω=I m ]
Since, θ–∅= – π/2
θ= – π/2 + ∅
We get,
I = I m cos(ωt–π/2+∅)
I = I m sin(ωt+∅)
Here, I m =V m /Z = V m / √R 2 +(X C –X L ) 2 and ∅=tan –1 (X C –X L /R)
- Thus, for θ=0 ∘ , As a result, the applied voltage and instantaneous current are in phase
- For θ=90 ∘ , The applied voltage is out of phase with the instantaneous current.
Resonance of LCR Circuit
If the output of a circuit reaches its maximum at a specific frequency, it is said to be in resonance. The resonance phenomenon is connected with systems that have a tendency to oscillate at a specific frequency known as the natural frequency of the system. The amplitude of oscillation is observed to be considered when an energy source drives such a system at a frequency close to the natural frequency.
![lcr series and parallel resonance experiment viva questions lcr series and parallel resonance experiment viva questions](https://media.geeksforgeeks.org/wp-content/uploads/20220417173748/SeriesResonance.jpg)
We discovered that the amplitudes of voltage, frequency, and current are related to each other in the following series of LCR circuits:
I m = V m /Z = V m / √R 2 +(X C –X L ) 2
where,
- X C =1/ωC and
I m =V m /Z=V m / √R 2 +(1/ωC−ωL) 2
When the circuit’s impedance is low, the current flowing through it is at its maximum. To accomplish so, we change the frequency value till we have X C =X L at a given frequency of ω 0 and the impedance,
Z=√ R 2 +(X C −X L ) 2 = √ R 2 +0 = R
Thus, the current will be maximum, i.e.,
When the series LCR circuit’s impedance, Z=R, equals the resistance. This frequency ω 0 is referred to as the circuit’s resonant frequency.
For, X C =X L
1/ω 0 C=ω 0 L
ω 0 = 1/√LC
Resonance occurs in a series LCR circuit when the capacitive and inductive reactances are equal in magnitude but 180 degrees apart in phase.
For the series LCR circuit, the phase difference,
∅=tan –1 (X C –X L / R)
For, X C =X L , ∅=0, the circuit is in resonance.
X C >X L , ∅<0, the circuit is predominately capacitive
X C <X L , ∅>0, the circuit is predominately inductive
Circuit Power Factor: The ratio of active power to total power is used to define the power of an AC circuit. i.e. Power Factor, CosΦ=Active power/Total Power CosΦ=I 2 R / I 2 Z =R/Z = R / √(R) 2 +(X L −X C ) 2
Power Consumed: The resistor is the sole component in the circuit that consumes power; the inductor and capacitor do not. Therefore, P=VI CosΦ =(IZ)×I×R/Z = I 2 R
Q – Factor of Series Resonant Circuit: The circuit’s Q-factor (Quality Factor) is defined as the ratio of reactive to active power, i.e. Q−factor = Reactive Power/Active Power Q−factor = I 2 X L /I 2 R = =I 2 X c /I 2 R Q−factor= ωL/R = 1/ωCR At resonance, ω 0 =1/√LC So, Q 0 −factor=1/R × √L/C
Sample Problems
Problem 1: In a series RLC, circuit R = 30 Ω, L = 15 mH, and C = 51 μF. If the source voltage and frequency are 12 V and 60 Hz, respectively, what is the current in the circuit?
X L = 2 × 3.14 × 60 × 0.015 = 5.655 Ω X C = 1/ 2 × 3.14 × 60 × 0.000051 = 5.655 Ω Z = √(30) 2 + (52-5.655) 2 = 55.21 Ω I = 12/55.21 = 217 mA
Problem 2: A series RLC circuit consists of a 20 Ω resistor, a 51 μF capacitor, and a 25 mH inductor. If the source frequency is 50 Hz, and the circuit current is 350 mA, what is the applied voltage?
Given that, R =20 Ω X L = 2 × 3.14 × 50 × 0.025 = 7.85 Ω X C = 1/ 2 × 3.14 × 50 × 0.000051 = 62.445 Ω Z= √(20) 2 + (7.85-62.445) 2 = 58.15 Ω V= IZ = 58.15 × 0.35 = 20 V
Problem 3: A 240 V, 50 Hz AC supply has applied a coil of 0.08 H inductance and 4 Ω resistance connected in series with a capacitor of 8 μF. Calculate the Impedance
Here, X L = ωL = 2πfL=2π×50×0.08=25.12 Ω X C =1/ωC=1/2πfL=1/2π×50×8×10 −6 = 398.09 Ω Thus, Impedance of the circuit Z=√(R) 2 +(X L −X C ) 2 = √(4) 2 +(25.12−398.09) 2 = 372.99 Ω
Conceptual Questions
Question 1: What is the resonance condition for the series LCR circuit?
The capacitive and inductive reactances are equal and 180 degrees out of phase at resonance.
Question 2: What is the impedance of the series LCR circuit?
The combined effects of ohmic resistance and reactance produce the effective resistance of an electric circuit or component to alternating current. The impedance of a series LCR circuit is expressed as, Z=√R 2 +(X C −X L ) 2
Question 3: What is the sharpness of resonance?
The Q factor determines the sharpness of resonance. The Q factor is a dimensionless parameter that describes the energy losses in a resonant element, such as a mechanical pendulum, a mechanical structure element, or an electronic circuit such as a resonant circuit. Q is frequently used in conjunction with an inductor. The sharpness of resonance is proportional to the rate at which the oscillating system’s energy decays.
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LCR Circuit : Analysis Of A LCR Series Circuit
In our article about the types of circuit , we discussed the two major types of circuit connection: Series and Parallel.
From the article, we understood that a series circuit is one in which the current remains the same along with each element . With this context, let us discuss the LCR circuit and its analysis in detail. An LCR circuit, also known as a resonant circuit, tuned circuit, or an RLC circuit, is an electrical circuit consisting of an inductor (L), capacitor (C) and resistor (R) connected in series or parallel . The LCR circuit analysis can be understood better in terms of phasors. A phasor is a rotating quantity.
![LCR Circuit LCR Circuit](https://cdn1.byjus.com/wp-content/uploads/2020/09/LCR-Circuit-Analysis-Of-A-LCR-Series-Circuit-1.png)
For an inductor (L), if we consider I to be our reference axis, then voltage leads by 90°, and for the capacitor, the voltage lags by 90°. But the resistance, current and voltage phasors are always in phase.
In this article, let us understand in detail about the RLC series circuit.
Following is the table explaining other related concepts of the circuit :
Analysis of An RLC Series Circuit
Let’s consider the following RLC circuit using the current across the circuit as our reference phasor because it remains the same for all the components in a series RLC circuit.
![LCR Circuit LCR Circuit](https://cdn1.byjus.com/wp-content/uploads/2020/09/LCR-Circuit-Analysis-Of-A-LCR-Series-Circuit-2.png)
As described above, the overall phasor will look like below:
![LCR Circuit LCR Circuit](https://cdn1.byjus.com/wp-content/uploads/2020/09/LCR-Circuit-Analysis-Of-A-LCR-Series-Circuit-3.png)
From the above phasor diagram, we know that,
The current will equal all three as it is a series LCR circuit. Therefore,
Using (1), (2), (3) and (4)
Also, the angle between V and I is known phase constant,
It can also be represented in terms of impedance,
Depending upon the values of X L and X C
We have three possible conditions,
- If X L > X c , then tan θ > 0 and the voltage leads the current and the circuit is said to be inductive
- If X L c , then tan θ < 0 and the voltage lags the current and the circuit is said to be capacitive
- If X L = X c , then tan θ = 0 and the voltage is in phase with the current and is known as resonant circuit.
Frequently Asked Questions – FAQs
Is there a difference between rlc circuit and lcr circuit, what are the phase differences between the current in the capacitor and the current in the resistor in a series lcr circuit, what is an rlc circuit, what is an inductor, what is a capacitor.
This was just an introduction to the LCR circuit. To know more about LCR circuits, types of circuits, inductance, capacitance, and resistance, download BYJU’S – The Learning App and fall in love with learning.
![lcr series and parallel resonance experiment viva questions lcr series and parallel resonance experiment viva questions](https://cdn1.byjus.com/wp-content/uploads/2021/09/RC-Circuit.jpg)
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Physics lab: Viva-Voce Question and Answers What is the total impedance in LCR circuit? How does it vary with frequency in case of both Series and Parallel LCR circuits. A: Z = √ [R 2 + ( XL- XC) 2 ] In Series LCR ckt., as the frequency increases current also increases but impedance decreases. At resonant frequency, current is maximum whereas impedance will be minimum. Further, increase in ...
In this video I explained the viva question and answer for the LCR series and parallel circuit.Step by step explanation has been given for a clear understand...
Most Important Questions from Series and Parallel LCR Circuits============================= Thanks for WatchingPlease leave a LIKE to Support me...😋 and don...
If the resistance increases/decreases, the value of maximum/minimum current at resonance in LCR series/parallel will decrease/increase. However the value of resonance frequency remains unaltered.
What all you need to know about LCR circuit?Learn important concepts of LCR series circuit easilyHello everyone,Welcome to the channel Solely Science ☺️So he...
Important LCR Circuit Questions with Answers 1) What is an LCR circuit? An LCR circuit is an electrical circuit composed of an inductor (L), a capacitor (C), and a resistor (R), connected in parallel or series. The circuit's name came from the letters that represent the respective components of this circuit.
Thus, the experiment observation clearly expresses the theory behind the series resonant circuit and the relationship between each individual component of the LCR circuit.
Frequently asked questions and answers of Series Parallel Resonance in Electronics Devices and Circuits of Electronics Engineering to enhance your skills, knowledge on the selected topic. We have compiled the best Series Parallel Resonance Interview question and answer, trivia quiz, mcq questions, viva question, quizzes to prepare.
L-C-R series and parallel circu. d the quality factorand. r, a variable capacitor, a variableinductor, a signal generator, an a.c. mill. actor Q = f 0 f - 2 f 1Where f1 and f2 are the f. When the resistor R, inductor L andcapacitor C are connected in series with a source of emf E , the circuit is called as the series resonant.
Find the readable practical file (with readings) of the above mentioned experiment at this link and some other useful links
This set of Microwave Engineering Multiple Choice Questions & Answers (MCQs) focuses on "Series and Parallel Resonant Circuits". 1. In a series LCR circuit, at resonance point the energy stored in the inductor and capacitor in the form of magnetic and electric energies are equal. a) True b) False View Answer 2.
Series LC Circuits. Switching our attention to series LC circuits, we experiment with placing significant resistances in parallel with either L or C. In the following series circuit examples, a 1 Ω resistor (R1) is placed in series with the inductor and capacitor to limit total current at resonance. The "extra" resistance inserted to ...
L /4. View Solution. In a series resonant LCR circuit, the voltage across R is 100 volts and R = 1 k with C = 2 . The resonant frequency is 200 rad/s. At resonance the voltage across L is. View Solution. In an LCR series a.c. circuit, the voltage across each of the components, L, C, and R is 50 V. The voltage across the LC combination will be.
This video covers the experiment of series and parallel resonance circuit and determining resonance and anti-resonance frequency.============================...
SERIES AND PARALLEL LCR CIRCUIT What is meant by resonance? It is a phenomenon in which frequency of the applied signal becomes equal to the frequency of the circuit. What do you mean by sharpness of resonance? The rate of growth or decay of current is called sharpness of the circuit.
Conceptual Questions Question 1: What is the resonance condition for the series LCR circuit? Answer: The capacitive and inductive reactances are equal and 180 degrees out of phase at resonance. Question 2: What is the impedance of the series LCR circuit? Answer: The combined effects of ohmic resistance and reactance produce the effective resistance of an electric circuit or component to ...
The difference this time however, is that a parallel resonance circuit is influenced by the currents flowing through each parallel branch within the parallel LC tank circuit. A tank circuit is a parallel combination of L and C that is used in filter networks to either select or reject AC frequencies. Consider the parallel RLC circuit below.
The quantity L has units of resistance Figure 2 shows the response of the series RLC circuit with L=47mH, C=47nF and for three different values of R corresponding to the under damped, critically damped and over damped case. We will construct this circuit in the laboratory and examine its behavior in more detail. Under Damped. R=500Ω Critically ...
LCR circuit consists of an inductor (L), capacitor (C) and resistor (R) connected in series or parallel. An LCR circuit is also known as a resonant circuit, tuned circuit, or RLC circuit.
Get The Series RLC Circuit Multiple Choice Questions (MCQ Quiz) with answers and detailed solutions. Download these Free The Series RLC Circuit MCQ Quiz Pdf and prepare for your upcoming exams Like Banking, SSC, Railway, UPSC, State PSC.
How do you resonant a LCR circuit? What happens in an RLC series circuit during resonance? What is series resonance? What is Q factor in LCR circuit? What is Q factor formula?
0 Series-Parallel Resonance uctor will have a resistive value. There are three methods for definin parallel resonance, each res ting in a different resonant frequency. For the parallel The frequency at which XL=XC. The frequency at which the parallel impedance is maximum. The frequency at which the current is in phase with the voltage.
Most likely questions and answers of LCR PARALLEL CIRCUIT experimentResonance in parallel LCRHello everyone,Welcome to Solely Science 😃Let's prepare ourselv...