# Network Theory 5

Electronic Engineering MCQ Question Papers: ENTC, IT Interview Placement

Subject:  Network Theory 5

Part 5: List for questions and answers of Network Theory

Q1. A two branch parallel tuned circuit has a coil of resistance 100 O and inductance 0.005 H in one branch and 10 nF capacitor in the second branch. At resonance frequency is

Q2. A capacitor used for power factor correction is single phase circuit decreases

a) Power factor

b) Line current

c) Both line current and p.f.

d) The line current and increases p.f.

Q3. A two branch tuned circuit has a coil of resistance R and inductance L in one branch and capacitance C in the second branch. If R is increased, the dynamic resistance

a) Increases

b) Decreases

c) Remains constant

d) May increases or decreases

Q4. A 1 µF capacitor is connected to 12 V battery. The energy stored in the capacitor is

a) 12 x 10^-6 J

b) 24 x 10^-6 J

c) 48 x 10^-6 J

d) 72 x 10^-6 J

Q5. The poles with greater displacement from the real axis correspond to

a) Higher frequencies of oscillation

b) Stable response

c) Lower frequencies of oscillation

d) Unbounded output

Q6. A constant k band pass filter has a pass band from 100 to 400 Hz. The resonant frequency of series and shunt arms is

a) 3000 Hz

b) 2500 Hz

c) 2000 Hz

d) 1500 Hz

Q7. Two similar coupled coils are connected in series. The total inductance in series aiding connection is 100 mH. If currents is 3 A, the energy stored in magnetic field is

a) 0.9 J

b) 0.45 J

c) 0.225 J

d) 1.8 J

Q8. Thevenin’s impedance of an ac network is in general

a) Resistance

b) R and L in series

c) R and C in series

d) Either R and L or R and C in series

Q9. An RLC series circuit has Q = 100 and ?0 = 20 rad/sec. The bandwidth is

Q10. In an unloaded transformer, the fluxes limiting the primary and secondary are 30 mWb and 20 mWb. The coefficient of coupling is

a) 1

b) 0.1

c) 0.33

d) 0.67

Q11. Poles and zeros of a driving point function of a network are simple and alternate on jω  axis. The network consists of

a) R and C

b) L and C

c) R and L

d) R, L and C

Q12. In a series RLC circuit the phase angle θ  of impedance Z ∠θ  is positive. The circuit will behave as

a) resistive circuit

b) RC circuit

c) RL circuit

d) Either RL or RC circuit

Q13. In a two terminals network the O.C. voltage measured at the given terminals is 100 V and s.c., currents at the same terminals 5 A. If a load of 80 O resistance is connected at the terminals, load current is

a) 1 A

b) 1.25 A

c) 6 A

d) 6.25 A

Q14. A coil has resistance R and inductance L. At ω  = 8 the phase angle between voltage and current is

a) 0°

b) 180°

c) 45°

d) 90°

Q15. An RLC series circuit has R = 7.07 O, L = .707 H and C = 7.07 µF. At Half power frequencies the circuit impedance is likely to be

a) 7.07 O

b) 10 O

c) 14.14 O

d) 20 O

Q16. Two similar coils have self inductance of 1 mH each. Coefficient of coupling is 0.5. The mutual inductance M is

a) 0.25 mH

b) 0.5 mH

c) 0.707 mH

d) 1 mH

Q17. A thermistor is used for

a) Over voltage protection

b) Temperature alarm circuit

c) Automatic light control

d) None of the above

Q18. When a lead acid battery is being charged, the specific gravity of the electrolyte

a) Decreases

b) Increases

c) Either increases or decreases

d) Remains the same

Q19. Which statement is true for an ac circuit?

a) Active power is always less than apparent power

b) Active power cannot be more than apparent power

c) Active power is always more than reactive power

d) Active power cannot be more than reactive power

Q20. Three inductors each 30 mH are connected in delta. The value of inductance or each arm of equivalent star is

a) 10 mH

b) 15 mH

c) 30 mH

d) 90 mH

Part 5: List for questions and answers of Network Theory