Electrical Circuits MCQ Solved Paper for FCI Recruitment

1. What is the complex impedance of a circuit with an absolute resistance of 300 ?
A. 0 + j 300
B. 300 + j 90
C. 0 ± j 300
D. 300 +j 0
Answer : D

2. Which of the following conditions is not true for a series RLCcircuit at resonance?
A. Z = jXL
B. XL= XC
C. The power factor is one
D. The magnitude of Z is
Answer : A

3. Which one of the following elements serves as a protection against overload?
A. Fuse
B. Switch
C. Resistor
D. Relay
Answer : A

4. How many degrees of phase represents one full cycle?
A.
B.
C.
D.
Answer : A

5. The superposition theorem is used when the circuit contains
A. Reactive elements
B. Active elements
C. Number of voltage sources
D. Single voltage source
Answer : C

6. The usual load of a dc circuit is a/an
A. Resistor
B. Capacitor
C. Inductor
D. Both inductor and capacitor
Answer : A

7. Transient period is considered over after
A.
B.
C.
D.
Answer : A

8. An inductive circuit of resistance 16.5 and inductance of 0.14 H takes a current of 25 ?. if the frequency is 50 Hza find the supply voltage.
A. 1501 V
B. 1174V
C. 1877V
D. 991 V
Answer : B

9. Which of the following does not generally affect the value of a capacitor?
A. The dielectric material used
B. The surface area of the plates
C. The thickness of the dielectric
D. The voltage applied to the plate
Answer : D

10. In a complex number 5 + j 10a 10 is called ___ part.
A. Imaginary
B. Real
C. Conjugate
D. Integer
Answer : A

11. What dielectric is generally employed by a variable capacitor?
A. Mica
B. Air
C. Electrolyte
D. Ceramic
Answer : B

12. Barium-strontium titanite dielectric material is also called
A. Ceramic
B. Polyster
C. Electrolytic
D. Bakelite
Answer : A

13. A wire of one kilometre length has a resistance of 20 . If the length is halveda then the new resistance is ___ the original resistance.
A. Half
B. Twice
C. One-fourth
D. Three times
Answer : A

14. For parallel capacitorsa total charge is
A. The sum of individual charges
B. Equal to the charge of either capacitors
C. Equal to the product of the charges
D. The quotient of the charges
Answer : A

15. What is a closed path made of several branches of the network called?
A. Junction
B. Node
C. Terminal
D. Loop
Answer : D

16. What is the reading of an ohmmeter for a shorted capacitor?
A. Zero
B. Infinity
C. k
D. M
Answer : A

17. If the capacitance of mica capacitor is 5 times the capacitcitora then the relative permittivity of mica is
A.
B.
C.
D.
Answer : B

18. What is the specific resistance of a pure germanium?
A. 55 -cm
B. 55 -m
C. 55 -mm
D. 55 k -m
Answer : A

19. A capacitor is used to
A. Block dc current
B. Pass dc current
C. Open voltage source
D. Short the voltage source
Answer : A

20. A capacitor opposes change in
A. Voltage
B. Current
C. Voltage and current
D. Neither voltage nor current
Answer : A

21. In a multiple capacitora the plate area is
A. Increased
B. The same
C. Decreased
D. Variable
Answer : A

22. The electric field strength between capacitor plates has a unit
A. Volts per meter
B. Volts per mil
C. Amperes per meter
D. Amperes per mil
Answer : A

23. When two in-phase sine waves that have identical frequency and amplitude are added togethera then the result is a sine wave with ___ the amplitude of either.
A. Half
B. Twice
C. Four times
D. One-fourth
Answer : B

24. In a rectangular wavea the peak factor is
A.
B.
C.
D.
Answer : D

25. What is the hot resistance of a 100 Wa 220 V incandescent lamp?
A.
B.
C.
D.
Answer : C

26. What is the cross-sectional are of a conductor whose diameter is 0.001 inch?
A. One micron
B. One angstrom
C. One steradian
D. One circular mil
Answer : D

27. For a linear circuita ___ voltage or current is used to calculate average power.
A. Rms
B. Peak
C. Average
D. Instantaneous
Answer : A

28. Refers specifically to steady state values of quantities in ac circuits which are complex numbers.
A. Domain
B. Scalar quantity
C. Vector quantity
D. Phasor quantity
Answer : D

29. A series-parallel combination of identical resistors will
A. Increase the power rating compared with one resistor alone
B. Increase the voltage rating compared with one resistor alone
C. Reduce the voltage rating compared with resistor alone
D. Result in an expensive circuit
Answer : A

30. A capacitance of 0.05 F equals
A. 0.05 x 106F
B. 0.05 x 10-6F
C. 0.05 x 10-12F
D. 0.05 x 1012F
Answer : B

31. A neon glow lamp used as a night light ionizes at approximately
A. 70 V
B. 80 V
C. 90 V
D. 100 V
Answer : A

32. The charge in the capacitor is stored at the
A. Terminals
B. Plates
C. Dielectric
D. Air
Answer : B

33. If two resistances of 9 and 6 are connected in parallela the total resistance is
A.
B.
C.
D.
Answer : D

34. What rating of a resistor determines its ability to absorb heat?
A. Wattage
B. Ohmic
C. Current
D. Voltage
Answer : A

35. Kirchhoff�s laws (KCL and KVL) are applicable to
A. DCcircuits
B. ACcircuits
C. DC as well as AC circuits
D. Passive networks alone
Answer : C

36. What can be used to estimate resonant frequency and to find reactance at any frequency for any value of capacitor or inductor?
A. Smith chart
B. Reactance chart
C. Impedance chart
D. Resonance chart
Answer : B

37. The hot resistance of an incandescent lamp is about ___ times its cold resistance.
A.
B.
C.
D.
Answer : A

38. An ac series circuit is composed of a resistance of 20 a inductive reactance of 40 a and a capacitive reactance of 15 . If a current of 1 ampere is flowinga what is the applied voltage
A. 320 V
B. 32 V
C. 220 V
D. 22 V
Answer : B

39. The ratio of W/VA in an ac circuit means
A. Power factor
B. Reactive factor
C. Quality factor
D. Load factor
Answer : A

40. The Q-factor of a parallel resonant circuit is also known as
A. Voltage magnification factor
B. Current magnification factor
C. Gain magnification factor
D. Resonance magnification factor
Answer : B

41. What is the peak factor of a triangular wave?
A.
B.
C.
D.
Answer : B

42. When two coils of identical reactance are in parallel without mutual inductancea the reactance of the combination is ___ the reactance of each coil.
A. One half
B. Twice
C. Four times
D. One fourth
Answer : A

43. Of the equivalent combination of unitsa which one is not equal to watt?
A. 2/V
B. AV
C. A2
D. J/s
Answer : A

44. The ohmic value of a resistor with negative temperature coefficient
A. Increases with increasing temperature
B. Increase with decreasing temperature
C. Stays unchanged with temperature change
D. Stays unaffected even with increasing temperature
Answer : B

45. What is the purpose of a load in an electric circuit?
A. To increase the circuit current
B. To decrease the circuit current
C. To utilize electrical energy
D. To make the circuit complete
Answer : C

46. Which of the following has negative temperature coefficient?
A. Carbon
B. Nickel
C. Brass
D. Constantan
Answer : A

47. A trigger circuit consisting of a capacitor of 0.01 F is connected in series with a resistor. If the circuit requires 100 Vdcto operatea determine the value of the resistor when time constant is 0.009s.
A.
B. 900 k
C. 900 M
D. 900 G
Answer : B

48. Which of the following elements is active?
A. Resistor
B. Inductor
C. Capacitor
D. Ideal voltage source
Answer : D

49. A circuit whose parameters change with voltage or current.
A. Non-linear circuit
B. Linear circuit
C. Complex circuit
D. Passive circuit
Answer : A

50. What is the peak factor for alternating current or voltage varying sinusiodally?
A.
B.
C.
D.
Answer : A