Question 1
Network TheoryResonance
The resonant angular frequency of an ideal series RLC circuit is?
Correct Answer: B. 1/sqrt(LC)
Explanation: At resonance XL = XC, giving omega0 = 1/sqrt(LC).
Reference: Standard network theory: resonance
Resonance MCQs
Practice Resonance MCQs with four options, answers and explanations for focused Electronics & Telecommunication Engineering revision.
Question 2
Network TheoryResonance
A series RLC circuit has L = 10 mH and C = 10 microfarad. Its resonant frequency is closest to?
Correct Answer: C. 503 Hz
Explanation: f0 = 1/(2πsqrt(LC)). With L=0.01 H and C=10^-5 F, f0 ≈ 503 Hz.
Reference: Standard network theory: resonance
Question 3
Network TheoryResonance
At resonance, the impedance of an ideal series RLC circuit reduces to?
Correct Answer: A. R
Explanation: At series resonance XL and XC cancel, leaving the net impedance equal to the resistance R.
Reference: Standard network theory: resonance
Question 4
Network TheoryResonance
At series resonance, the power factor of an ideal RLC circuit is?
Correct Answer: C. Unity
Explanation: At resonance the net reactance is zero, so voltage and current are in phase and power factor is unity.
Reference: Standard network theory: resonance
Question 5
Network TheoryResonance
A series resonant circuit has resonant frequency 10 kHz and bandwidth 500 Hz. Its quality factor Q is?
Correct Answer: B. 20
Explanation: For a series resonant circuit, Q = f0/BW = 10000/500 = 20.
Reference: Standard network theory: resonance
Question 6
Network TheoryResonance
A series RLC circuit has R = 20 ohm, L = 0.2 H and C = 50 microfarad. Its resonant frequency is closest to?
Correct Answer: B. 50.3 Hz
Explanation: f0 = 1/(2π√LC). Here LC = 0.2×50×10^-6 = 10^-5, so f0 ≈ 50.3 Hz.
Reference: Standard network theory: resonance
Question 7
Network TheoryResonance
For the same series RLC circuit with R = 20 ohm, L = 0.2 H and C = 50 microfarad, its quality factor Q = omega0 L/R is closest to?
Correct Answer: C. 3.16
Explanation: omega0 = 1/√LC ≈ 316.2 rad/s. Therefore Q = 316.2×0.2/20 ≈ 3.16.
Reference: Standard network theory: resonance
Question 8
Network TheoryResonance
A series RLC circuit has R = 10 ohm and L = 0.1 H. Its bandwidth in rad/s is R/L, equal to?
Correct Answer: B. 100 rad/s
Explanation: For a series RLC circuit, bandwidth in angular frequency is Δomega = R/L = 10/0.1 = 100 rad/s.
Reference: Standard network theory: resonance
Question 9
Network TheoryResonance
At parallel resonance in an ideal parallel RLC circuit, the input impedance is ideally?
Correct Answer: B. Maximum
Explanation: At parallel resonance the reactive branch currents cancel at the input, making the input admittance minimum and impedance maximum in the ideal case.
Reference: Standard network theory: resonance
Question 10
Network TheoryResonance
For a parallel RLC circuit at ideal resonance, the input susceptance is?
Correct Answer: C. Zero
Explanation: At parallel resonance, inductive and capacitive susceptances cancel, leaving zero net susceptance.
Reference: Standard network theory: parallel resonance
Question 11
Network TheoryResonance
A series RLC circuit has R=10 ohm, L=0.1 H and C=100 microfarad. Its quality factor at resonance is approximately?
Correct Answer: B. 3.16
Explanation: For a series RLC circuit, Q=omega0 L/R=sqrt(L/C)/R. sqrt(0.1/100e-6)=sqrt(1000)=31.62, so Q≈3.16.
Reference: Standard network theory: series resonance Q
Question 12
Network TheoryResonance
A series resonant circuit has resonant frequency 10 kHz and quality factor Q=20. Its bandwidth is?
Correct Answer: A. 0.5 kHz
Explanation: For a resonant circuit, Q=f0/BW, so BW=10 kHz/20=0.5 kHz.
Reference: Standard network theory: resonance bandwidth
Question 13
Network TheoryResonance
At the half-power frequencies of a series RLC circuit, the current magnitude is approximately what fraction of its resonant maximum value?
Correct Answer: B. 0.707
Explanation: At the half-power points, power is half its maximum value, so current magnitude is 1/sqrt(2)≈0.707 of the resonant current.
Reference: Standard network theory: half-power frequencies