Network Theory Practice Test 4

1. The value of ω_r in parallel resonant circuit is?

1/(π√LC)

1/(2√LC)

1/√LC

1/(2π√LC)

2. Find the voltage across (2+j5) Ω impedance considering 50∠0⁰ voltage source.

30.16∠9.28⁰

30.16∠-9.28⁰

29.16∠9.28⁰

29.16∠-9.28⁰

3. As X_L = X_C in a series resonance circuit, the impedance is_________

purely inductive

purely capacitive

capacitive and inductive

purely resistive

4. Find the bandwidth of the circuit shown below.

5. The expression of quality factor is?

I_L/I

I/I_L

6. In series circuits, the expression for quality factor is?

f_r

BW/f_r

f_r/BW

7. Consider a circuit consisting of two capacitors C₁ and C₂. Let R be the resistance and L be the inductance which are connected in series. Let Q₁ and Q₂ be the quality factor for the two capacitors. While measuring the Q value by the Series Connection method, the value of the Q factor is?

Q = \(\frac{(C_2 - C_1) Q_1 Q_2}{Q_1 C_1-Q_2 C_2}\)

Q = \(\frac{(C_2 - C_1) C_1 C_2}{Q_1 C_1-Q_2 C_2}\)

Q = \(\frac{(C_1 - C_2) Q_1 Q_2}{Q_1 C_1-Q_2 C_2}\)

Q = \(\frac{(C_1 - C_2) Q_1 Q_2}{Q_2 C_2-Q_1 C_1}\)

8. A series RLC circuit has a resonance frequency of 1 kHz and a quality factor Q = 50. If R and L are doubled and C is kept same, the new Q of the circuit is?

20.02

25.52

35.35

45.45

9. For a parallel RLC circuit, the incorrect statement among the following is _____________

At resonance, input impedance is a real quantity

The bandwidth of the circuit decreases if R is increased

The bandwidth of the circuit remains same if L is increased

At resonance, the magnitude of input impedance attains its minimum value

10. An ideal transformer is rated as 2400/120 V, 9.6 kVA and has 50 turns on the secondary side. The turns ratio is ____________

0.07

0.05

0.04

0.06