1000+ Electrical Circuits Multiple Choice Question Answer [Solved]

1. According to Gauss theorema flux can be equated to
A. Charge
B. Field intensity
C. Current
D. Voltage
Answer : A

2. In liquids and gasesa ionization current results from a flow of
A. Positive or negative ions
B. Free electrons
C. Ions that are lighter in weight than electrons
D. Protons
Answer : B

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

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

5. The Q-factor of a series resonant circuit is also known as
A. Current magnification factor
B. Voltage magnification factor
C. Load factor
D. Leakage factor
Answer : B

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

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

8. Which is considered as the effect of a dielectric material?
A. Increasing capacitance
B. Decreasing capacitance
C. Reducing the working voltage
D. Increasing the distance between the plates
Answer : A

9. What is considered as the most important value of a sine wave?
A. Effective value
B. Peak value
C. Average value
D. Instantaneous value
Answer : A

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

11. Capacitance increase with
A. Larger plate area and less distance between plates
B. Larger plate area and greater distance between plates
C. Smaller plate area and less distance between plates
D. Higher values of applied voltage
Answer : A

12. What is the resonant frequency of a circuit when L of 3 microhenrys and C of 40 picofarads are in series?
A. 14.5 kHz
B. 145 MHz
C. 14.5 MHz
D. 145 kHz
Answer : C

13. 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

14. How many coulombs are delivered by a storage battery in 25 hours if it is supplying current at the rate of 3 A?
A. 2.592 x 105C
B. 2.592 x 103 C
C. 2.592 x 108 C
D. 2.592 x 1012 C
Answer : A

15. The capacitor opposes any change in voltage across it by
A. Passing a voltage proportional to the rate of change of current
B. Acting as a short circuit at time equal to zero
C. Passing a current proportional to the rate of change of voltage
D. Acting as a short circuit at time equal to infinity
Answer : C

16. The admittance of a parallel RLC circuit is found to be the ___ sum of conductance and susceptances.
A. Algebraic
B. Arithmetic
C. Vector
D. Phasor
Answer : D

17. At what frequency will an inductor of 5mH have the same reactance as a capacitor of 0.1 F?
A. 7.12 kHz
B. 7.12 Hz
C. 7.12MHz
D. 7.12 GHz
Answer : A

18. Form its definitiona the unit of electric fielda is the N/C and equivalent unit of is the
A. V(m)2
B. V(m)
C. V/m2
D. V/m
Answer : D

19. The ratio between the active power and the apparent power of a load in an ac circuit is called
A. Quality factor
B. Power factor
C. Power ratio
D. Power reactive
Answer : B

20. And ideal current source has an internal conductance of _____ siem
A. Infinite
B. One
C. Zero
D. One million
Answer : C

21. 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

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

23. Which of the following dielectric materials makes the lowest-capacitance capacitor?
A. Paper
B. Mica
C. Air
D. Electrolyte
Answer : C

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

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

26. What increases the resistance of wire at high frequencies?
A. Temperature
B. Voltage
C. Skin effect
D. Insulation
Answer : C

27. An open inductor has
A. Zero resistance and infinite inductance
B. Infinite resistance and zero inductance
C. Infinite resistance and infinite inductance
D. Zero resistance and zero inductance
Answer : B

28. At what frequency will the current in a series RLCcircuit reach its maximum value for an applied voltage of 15 V with R = 500 a L = 100 H and C= 0.001 F?
A. 503 kHz
B. 403 kHz
C. 603 kHz
D. 303 kHz
Answer : A

29. What is the temperature coefficient of the resistance Eureka?
A. Infinity
B. Negative
C. Almost zero
D. Positive
Answer : C

30. 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

31. For a triangular and sawtooth waveform the rms voltage or current equals
A. 0.707times peak value
B. 0.577 times peak value
C. 0.577times average value
D. 0.707times rms value
Answer : B

32. Resistor with colored bands in the body
A. Wire-wound resistor
B. Carbon-composition resistor
C. Potentiometer
D. Rheostat
Answer : B

33. Which of the following dielectric materials makes the highest-capacitance capacitor?
A. Air
B. Barium-strontium titanite
C. Mica
D. Electrolyte
Answer : B

34. A 5 F capacitor charge to 5V has a stored charge equal to
A. 1 c
B. 5 c
C. 25 C
D. 200 c
Answer : C

35. The open-circuit voltage at the terminal of load RL is 60V. Under the condition of maximum power transfera the load voltage will be
A. 60 V
B. 15 V
C. 20 V
D. 30 V
Answer : D

36. In a series RLCcircuit
A. Increasing the frequency decreases the resistance
B. Increasing the frequency increases the resistance
C. Both XLand XCchange as frequency changes
D. Impedance will always decrease
Answer : C

37. Which of the following capacitors are used only in dc circuits?
A. Mica
B. Ceramic
C. Mylar
D. Electrolytic
Answer : D

38. Permeability is otherwise known as
A. Magnetic conductivity
B. Magnetic susceptibility
C. Electric conductivity
D. Electric susceptibility
Answer : A

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

40. In the 5-band method of capacitor color codinga the first band indicates
A. Temperature coefficient
B. Tolerance
C. 1stdigit
D. Capacitance value
Answer : A

41. What is expected when two 20 k a 1 watt resistor in parallel are use instead of one 10 k a 1 watt?
A. Provides higher current
B. Provides less power
C. Provides more power
D. Provides wider tolerance
Answer : C

42. What is the other name of relative permittivity?
A. Dielectric strength
B. Potential gradient
C. Breakdown voltage
D. Specific inductance capacity
Answer : D

43. A series RL circuit has R of 10 and XL of 5 a its impedance in rectangular form is given by
A. 10 +j 5
B. 10 + j 10
C. 10 ± j 5
D. 10 ± j 10
Answer : A

44. Which of the following is a preferred resistor value?
A.
B.
C. 43a000
D. 54a321
Answer : B

45. 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

46. If two equal resistances connected in series across a certain supply are now connected in parallel across the same supplya the power produced will be _____ that of series connection
A. One-half
B. One-fourth
C. Two times
D. Four times
Answer : D

47. Which component opposes voltage change?
A. Resistor
B. Inductor
C. Capacitor
D. Transistor
Answer : C

48. When the power factor of a circuit is zeroa
A. Power absorbed is maximum
B. Power absorbed is minimum
C. Power absorbed is zero
D. The impedance is minimum
Answer : C

49. The power factor of a circuit is equal to
A. RZ
B. XC/Z
C. XL/Z
D. R/Z
Answer : D

50. Which of the following combination of length and cross-sectional area will give a certain volume of copper the least resistance?
A. 2L and1/2 A
B. Does not matter because the volume of copper remains the same
C. L and A
D. ½ L and 2 A
Answer : D