250+ TOP MCQs on Parallel Resonance and Answers

Network Theory Multiple Choice Questions on “Parallel Resonance”.

1. For the circuit shown below, determine its resonant frequency.
A. 6.12
B. 7.12
C. 8.12
D. 9.12

Answer: B
Clarification: The resonant frequency of the circuit is f_r = 1/(2π√LC.. Given L = 5H and C = 100uf. On substituting the given values in the equation we get resonant frequency = 1/(2π√(5×100×10^-6)) = 7.12 Hz.

2. Find the quality factor of the following circuit.
A. 2.24
B. 3.34
C. 4.44
D. 5.54

Answer: A
Clarification: The quality factor of the circuit is Q = X_L/R = 2πf_rL/R. Given f = 7.12 Hz and L = 5H and R = 100. On substituting the given values in the equation we get the quality factor = (6.28×7.12×5)/100 = 2.24.

3. Find the bandwidth of the circuit shown below.

A. 1
B. 2
C. 3
D. 4

Answer: C
Clarification: The bandwidth of the circuit is BW = f_r/Q. we obtained f_r = 7.12 Hz and Q = 2.24. On substituting the given values in the equation we get the bandwidth = 7.12/2.24 = 3.178Hz.

4. The magnification in resonance considering the voltage across inductor is?
A. V/V_L
B. V_L/V
C. V x V_L
D. V_L

Answer: B
Clarification: The ratio of voltage across inductor to the voltage applied at resonance can be defined as magnification. The magnification in resonance considering the voltage across inductor is Q = V_L/V.

5. Considering the voltage across the capacitor, the magnification in resonance is?
A. V_C
B. V x V_C
C. V_C/V
D. V/V_C

Answer: C
Clarification: The ratio of voltage across capacitor to the voltage applied at resonance can be defined as magnification. Considering the voltage across the capacitor, the magnification in resonance is Q = V_C/V.

6. The value of ω_r in parallel resonant circuit is?
A. 1/(2√LC.
B. 1/√LC
C. 1/(π√LC.
D. 1/(2π√LC.

Answer: B
Clarification: Basically parallel resonance occurs when X_L = X_L. The frequency at which the resonance occurs is called the resonant frequency. The value of ω_r in parallel resonant circuit is ω_r = 1/√LC.

7. The expression of resonant frequency for parallel resonant circuit is?
A. 1/(2π√LC.
B. 1/(π√LC.
C. 1/(2√LC.
D. 1/√LC

Answer: A
Clarification: The condition for resonance occurs when X_L = X_L. The expression of resonant frequency for parallel resonant circuit is f_r = 1/(2π√LC..

8. Find the resonant frequency in the ideal parallel LC circuit shown in the figure.
A. 7.118
B. 71.18
C. 711.8
D. 7118

Answer: D
Clarification: The expression for resonant frequency is f_r = 1/(2π√LC.. Given L = 50mH and C = 0.01uF. On substituting the given values in the equation we get the resonant frequency = 1/(2π√(50×10^-3)×0.01×10^-6))=7117.6 Hz.

9. If the value of Q of the circuit is high, then its effect on bandwidth is?
A. large bandwidth
B. small bandwidth
C. no effect on bandwidth
D. first increases and then decreases

Answer: B
Clarification: If the value of Q of the circuit is high, then small bandwidth because bandwidth is inversely proportional to the quality factor.

10. If in a circuit, if Q value is decreased then it will cause?
A. small bandwidth
B. no effect on bandwidth
C. first increases and then decreases
D. large bandwidth

Answer: D
Clarification: If in a circuit, if the Q value is decreased then bandwidth increases and the bandwidth do not decrease.