1000+ Electrical Circuits Multiple Choice Question Answer [Solved]

1. In Norton�s theorema the short circuit current is obtained by
A. Opening the load terminals
B. Shorting the load terminals
C. Opening the voltage source
D. Shorting the voltage source
Answer : B

2. When voltage is applied across a ceramic dielectric the electrostatic field p roduced is 50 times greater than air dielectric. The dielectric constant of ceramic therefore is
A.
B.
C.
D.
Answer : A

3. 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

4. Two capacitors of capacitance 9 F and 18 F in series will have a total capacitance of
A. 27 F
B. 162 F
C. 6 F
D. 180 F
Answer : C

5. The voltage cannot be exactly in phase with the current in a circuit that contains
A. Only capacitance
B. Only resistance
C. Inductance and capacitance
D. Inductancea capacitance and resistance
Answer : A

6. Tungsten filament of bulbs has a hot resistance higher than its cold resistance due to its temperature coefficient which is
A. Positive
B. Negative
C. Zero
D. Infinite
Answer : A

7. What is the rms value of a square wave?
A. Equals its peak value
B. Equals its peak-to-peak value
C. Peak divided by square root of two
D. Peak divided by pi
Answer : A

8. Thevenin�s theorem is what form of an equivalent circuit?
A. Current
B. Voltage
C. Both current and voltage
D. Neither current nor voltage
Answer : B

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

10. 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

11. Which of the following is not a factor affecting capacitance oor?
A. Area of plates
B. Number of plates
C. Distance between plates
D. Dielectric material used
Answer : B

12. Which of the following capacitors is suitable for dc filter circuits?
A. Mica
B. Ceramic
C. Paper
D. Electrolytic
Answer : D

13. When resistance are connected in parallela the total resistance is
A. Less than the smallest resistance in the connection
B. Greater than the smallest resistance in the connection
C. Between the smallest and greatest resistance in the connection
D. Increasing and decreasing depending upon the supply voltage
Answer : A

14. A series RLCcircuit consists of a 10 resistor in series with L = 10 Ha and C= 100 F. Determine a new value of Ia for which the resonant frequency is one ±half the original value.
A. 40 H
B. 40 mH
C. 40 pH
D. 40 nH
Answer : A

15. When the movable plates of a gang capacitor completely overlap the fixed platesa the capacitance of the capacitor is
A. Halfway between maximum and minimum
B. Maximum
C. Minimum
D. Zero
Answer : B

16. An alloy composed of 84 % coppera 12 % manganese and 4 % nickel.
A. Manganin
B. Constantan
C. Nichrome
D. German silver wire
Answer : A

17. When two complex conjugates are subtracteda the result is a
A. Quadrature component only
B. Complex component
C. In-phase component
D. Real component
Answer : A

18. For a carbon composition resistora typical resistance values range from
A. 2.7 to 22 M
B. 1000 to 10000
C. 10 to 10 M
D. 2.7 to 2.7G
Answer : A

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

20. 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

21. The farad is not equivalent to which of the following combination of units
A. CV2
B. C2/J
C. C/V
D. J/V2
Answer : A

22. Which of the following is a disadvantage of a wire-wound resistor?
A. It has reactance in radio-frequency circuits
B. It cannot handle much power
C. It draws a large amount of current
D. It cannot handle high voltage
Answer : A

23. The symbol Q refers to
A. Resonance quotient
B. Quality factor
C. Power quotient
D. Qualification test
Answer : B

24. Leakage resistance in a capacitor results into
A. Internal heating
B. Internal bleeding
C. Shorter useful life
D. Short-circuiting
Answer : A

25. 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

26. Which of the following is the most popular waveform?
A. Sinusoidal
B. Square wave
C. Triangular
D. Sawtooth
Answer : A

27. The rms value of a triangular or sawtooth waveform is ___ tim value.
A.
B.
C.
D.
Answer : A

28. The presence of an electric current is made known by
A. Electric shock
B. Effects produced
C. Magnetic shock
D. Flashing
Answer : B

29. The distance between the capacitor plates increases two timesa then its capacitance
A. Increases two times
B. Increases four times
C. Decreases two times
D. Decreases four times
Answer : C

30. With double the number of turns by the same length and areaa the inductance is
A. The same
B. Doubled
C. Quartered
D. Quadrupled
Answer : D

31. The result of rust in electrical (wire) connection is
A. Inductance
B. Conductance
C. Impedance
D. Resistance
Answer : D

32. A resistor wound with a wire doubled back on itself to reduce the inductance.
A. Bifilar resistor
B. Wire-wound resistor
C. Anti-inductive resistor
D. Bleeder resistor
Answer : A

33. The internal resistance of an ideal current source is
A. Infinite
B. Zero
C. Equal to the load resistance
D. To be determined
Answer : A

34. A capacitor requires 12 C of charge to raise its potential of 3 V. What is the capacitance of the capacitor?
A. 36 F
B. 15 F
C. 0.25 F
D. 4 F
Answer : D

35. What is the total effective capacitance of two 0.25 F capacitors connected in series?
A. 0.125 F
B. 1.25 F
C. 0.50 F
D. 2.5 if
Answer : A

36. Electric energy refers to
A. Volt divided by coulomb
B. Voltampere
C. Volt-coulomb
D. Watt divided by time
Answer : C

37. Effects of capacitance
A. It opposes any change in the amount of voltage
B. Voltage is lagged behind the current by a quarter cycle
C. Electric energy is stored in the capacitor in the form of electrostatic field
D. All of the above
Answer : D

38. What fusion of elements is without chemical action between them?
A. Mixture
B. Compound
C. Alloy
D. Ionization
Answer : C

39. 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

40. Another term for superconductor.
A. Generic conductor
B. Ultraconductor
C. Cryotron
D. Cryogenic conductor
Answer : D

41. What is the time constant for L of 240 mH in series with R of 20 ?
A. 12 ms
B. 4.8 s
C. 83.3 s
D. 12 s
Answer : A

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

43. The value of temperature coefficient ( ) is dependent upon
A. The nature of material and temperature
B. The length of material
C. The cross-sectional area of the material
D. The volume of the material
Answer : A

44. For greater accuracya the value of phase angle should be determined from
A. Cos
B. Tan
C. Sin
D. Sec
Answer : B

45. A switch designed to have low capacitance between its terminal when open.
A. LOCAP switch
B. AntiLOCAP switch
C. Anticapacitance switch
D. Capacitance switch
Answer : C

46. What is the most common non-sinusoidal waveform?
A. Square wave
B. Triangular wave
C. Trapezoidal wave
D. Sawtooth wave
Answer : A

47. An electric circuit contains
A. Passive elements
B. Active elements
C. Both active and passive elements
D. Reactive elements
Answer : C

48. Which of the following represents the energy stored in a cap
A. CV2/2
B. 2Q2/C
C. C2/V
D. CV
Answer : A

49. In an ac wavea 30 degrees of phase is ___ of a cycle.
A. ½
B.
C.
D.
Answer : B

50. When capacitors are connected in parallela the total capacitance is
A. Greater than the largest capacitor
B. Smaller than the largest capacitor
C. Smaller than the smallest capacitor
D. Greater than the smallest capacitor
Answer : A