100+ Current Electricity Questions

                     

1. Which of the following elements of electrical engineering cannot be analyzed using Ohm’s law?
a) Capacitors
b) Inductors
c) Transistors
d) Resistance
Answer: c

2. What is constant for a charged spherical shell according to basic electrical energy?
a) Electrical potential outside the spherical shell
b) Electrical potential inside the spherical shell
c) Electrical field outside the spherical shell
d) Electrical field inside the spherical shell
Answer: b

3. Where does electro-static shielding occur in a charged spherical shell?
a) When electrical potential outside spherical shell is zero
b) When electrical potential inside the spherical shell is zero
c) When electrical field outside the spherical shell
d) Electrical field inside the spherical shell
Answer: d

4. Which of the following is a correct representation of peak value in an AC Circuit?
a) RMS value/Peak factor
b) RMS value*Form factor
c) RMS value/Form factor
d) RMS value*Peak factor
Answer: d

5. Which of the following according to fundaments of electrical energy is correct about alternating current?
a) Frequency is zero
b) Magnitude changes with time
c) Can be transported to larger distances with less loss in power
d) Flows in both directions
Answer: a

6. How many cycles will an AC signal make in 2 seconds if its frequency is 100 Hz?
a) 50
b) 100
c) 150
d) 200
Answer: d

7. What will be the direction of the drift velocity of electrons change with respect to the electric field?
a) same as that of electric field
b) opposite to that of electric field
c) perpendicular to that of the electric field in a positive direction
d) perpendicular to that of the electric field in a negative direction
Answer: b

8. What will be the current density of metal if a current of 30A is passed through a cross-sectional area of 0.5m2?
a) 7.5 A/m2
b) 15 A/m2
c) 60 A/m2
d) 120 A/m2
Answer: c

9. Which of the following is correct about the power consumed by R1 and R2 connected in series if the value of R1 is greater than R2?
a) R1 will consume more power
b) R2 will consume more power
c) R1 and R2 will consume the same power
d) The relationship between the power consumed cannot be established
Answer: a

10. What is zero for a charged spherical shell?
a) Electrical potential outside the spherical shell
b) Electrical potential inside the spherical shell
c) Electrical field outside the spherical shell
d) Electrical field inside the spherical shell
Answer: d

11. What kind of quantity is an Electric potential?
a) Vector quantity
b) Tensor quantity
c) Scalar quantity
d) Dimensionless quantity
Answer: c

12. What do crowded lines of force indicate?
a) Strong electric field
b) Weak electric field
c) Strong electric potential
d) Weak electric potential
Answer: a

13. What is the direction of the electric field at a point?
a) Along the line perpendicular to the electric field
b) Along the line tangent to the electric field
c) Electric field has no direction
d) Electric field has a random direction
Answer: b

14. What is the magnitude of mutually induced emf, E2 in a transformer?
a) directly proportional to rate of change of flux and number of secondary turns
b) inversely proportional to rate of change of flux and number of secondary turns
c) proportional to rate of change of flux and inversely proportional to number of secondary turns
d) inversely proportional to the rate of change of flux and proportional to number of secondary turns
Answer: a

15. Which of the following will happen in a transformer when the number of secondary turns is less than the number of primary turns?
a) The voltage gets stepped up
b The voltage gets stepped down
c) The power gets stepped up
d) The power gets stepped down
Answer: b

16. What is the number of primary turns in a 200/1000 V transformer if the emf per turn is 10V?
a) 5
b) 10
c) 20
d) 40
Answer: c

17. Which of the following is a correct representation of average value in an AC Circuit?
a) RMS value/Form factor
b) RMS value*Form factor
c) RMS value/Peak factor
d) RMS value*Peak factor
Answer: a

18. Who defined electric current and devised a method to measure current?
a) Michael Faraday
b) Andre-Marie Ampere
c) Nikola Tesla
d) Alessandro Antonio Volta
Answer: b

19. How many electrons will constitute 2 Coulombs of electric charge?
a) 6.24 * 1018 electrons
b) 12.48 * 1018 electrons
c) 1.602 * 1019 electrons
d) 3.204 * 1019 electrons
Answer: b

20. Which of the following is correct about direct current?
a) Magnitude is constant
b) Frequency is zero
c) Can be transported to larger distances with less loss in power
d) Flows in one direction
Answer: c

21. Who witnessed the effect of magnetism for the first time?
a) Hans Christian Orsted
b) Alexander Graham Bell
c) Michael Faraday
d) Gustav Robert Kirchhoff
Answer: a

22. Which of the following according is correct about electrical conductivity?
a) It is the ratio of current density to the electric field
b) It is the product of current density and electric field
c) It is the ratio of the electric field to current density
d) It is the reciprocal of the product of current density and electric field
Answer: a

23. What is responsible for the current to flow?
a) Protons
b) Electrons
c) Nucleus
d) Protons and Electrons
Answer: b

24. Which of the following according to KCL must be zero?
a) Algebraic sum of currents in closed-loop
b) Algebraic sum of power in closed-loop
c) Algebraic sum of currents entering and leaving a junction
d) Algebraic sum of voltages across the input and output
Answer: c

25. How many directions can the electric field at a point have?
a) Zero
b) One
c) Two
d) Many
Answer: b

26. Which of the following will happen in a transformer when the number of secondary turns is greater than the number of primary turns?
a) The voltage gets stepped up
b) The voltage gets stepped down
c) The power gets stepped up
d) The power gets stepped down
Answer: a

27. Which of the following is correct about the voltage transformation ratio in electrical engineering?
a) Ratio of number of primary turns to the number of secondary turns
b) Ratio of induced emf in secondary to induced emf in primary
c) Ratio of secondary current to the primary current
d) Ratio of power in primary to power in secondary
Answer: b

28. Which of the following according to the fundamentals of electrical engineering is correct about the induced emf in primary of transformer?
a) It is the ratio of primary turns to emf induced per turn
b) It is the product of primary turns and emf induced per turn
c) It is the ratio of secondary turns to emf induced per turn
d) It is the product of secondary turns and emf induced per turn
Answer: b

29. Which of the following current is drawn by the primary circuit of an ideal transformer when the secondary is open?
a) Secondary current
b) Leakage current
c) Magnetizing current
d) Working on current
Answer: c

30. What does positive power in an electrical element indicate?
a) Element is absorbing power
b) Element is supplying power
c) Element may absorb or supply power
d) Element is neither absorbing nor supplying power
Answer: a

31. How does induce emf in DC motor react to supply voltage?
a) It will aid the supply voltage
b) It will be double the supply voltage
c) It will oppose the supply voltage
d) It will be half of the supply voltage
Answer: c

32. Which of the following type of circuits in electrical engineering cannot be analyzed using Ohm’s law?
a) Unilateral
b) Bilateral
c) Linear
d) Conductors
Answer: a

33. Which of the following according to KVL must be zero?
a) Algebraic sum of currents in closed-loop
b) Algebraic sum of power in closed-loop
c) Algebraic sum of losses in closed-loop
d) Algebraic sum of voltages in closed-loop
Answer: d

34. Find the current in the circuit.


a) 1 A
b) 2 A
c) 3 A
d) 4 A
Answer: b

35. In a series circuit, which of the parameters remain constant across all circuit elements such as resistor, capacitor and inductor etcetera?
a) Voltage
b) Current
c) Both voltage and current
d) Neither voltage nor current
Answer: b

36. Voltage across the 60ohm resistor is______

a) 72V
b) 0V
c) 48V
d) 120V
Answer: b

37. Find the voltage across the 6 ohm resistor.

a) 150V
b) 181.6V
c) 27.27V
d) 54.48V
Answer: c

38. If there are two bulbs connected in series and one blows out, what happens to the other bulb?
a) The other bulb continues to glow with the same brightness
b) The other bulb stops glowing
c) The other bulb glows with increased brightness
d) The other bulb also burns out
Answer: b

39. What is the value of x if the current in the circuit is 5A?

a) 15 ohm
b) 25 ohm
c) 55 ohm
d) 75 ohm
Answer: a

40. A voltage across a series resistor circuit is proportional to?
a) The amount of time the circuit was on for
b) The value of the resistance itself
c) The value of the other resistances in the circuit
d) The power in the circuit
Answer: b

41. Many resistors connected in series will?
a) Divide the voltage proportionally among all the resistors
b) Divide the current proportionally
c) Increase the source voltage in proportion to the values of the resistors
d) Reduce the power to zero
Answer: a

42. What is the voltage measured across a series short?
a) Infinite
b) Zero
c) The value of the source voltage
d) Null
Answer: b

43. What happens to the current in the series circuit if the resistance is doubled?
a) It becomes half its original value
b) It becomes double its original value
c) It becomes zero
d) It becomes infinity
Answer: a

44. If two bulbs are connected in parallel and one bulb blows out, what happens to the other bulb?
a) The other bulb blows out as well
b) The other bulb continues to glow with the same brightness
c) The other bulb glows with increased brightness
d) The other bulb stops glowing
Answer: b

45. Calculate the current across the 20 ohm resistor.

a) 10A
b) 20A
c) 6.67A
d) 36.67A
Answer: a

46. In a parallel circuit, with a number of resistors, the voltage across each resistor is ________
a) The same for all resistors
b) Is divided equally among all resistors
c) Is divided proportionally across all resistors
d) Is zero for all resistors
Answer: a

47. The current in each branch of a parallel circuit is proportional to _________
a) The amount of time the circuit is on for
b) Proportional to the value of the resistors
c) Equal in all branches
d) Proportional to the power in the circuit
Answer: b

48. Calculate the total current in the circuit.

a) 20 A
b) 10 A
c) 11.43 A
d) 15 A
Answer: c

49. The voltage across the open circuit is?

a) 100V
b) Infinity
c) 90V
d) 0V
Answer: a

50. The voltage across the short is?

a) 135V
b) Infinity
c) Zero
d) 11.25V
Answer: c

51. If the current through x ohm resistance in the circuit is 5A, find the value of x.

a) 27 ohm
b) 5 ohm
c) 12 ohm
d) 135 ohm
Answer: a

52. The currents in the three branches of a parallel circuit are 3A, 4A and 5A. What is the current leaving it?
a) 0A
b) Insufficient data provided
c) The largest one among the three values
d) 12A
Answer: d

53. The total resistance between A and B are?

a) 20 ohm
b) 5 ohm
c) 80 ohm
d) 0 ohm
Answer: b

54. It is preferable to connect bulbs in series or in parallel?
a) Series
b) Parallel
c) Both series and parallel
d) Neither series nor parallel
Answer: b

55. Calculate the total resistance between the points A and B.

a) 7 ohm
b) 0 ohm
c) 7.67 ohm
d) 0.48 ohm
Answer: c

56. Calculate the equivalent resistance between A and B.

a) 60 ohm
b) 15 ohm
c) 12 ohm
d) 48 ohm
Answer: c

57. Calculate the resistance between A and B.

a) 3.56 ohm
b) 7 ohm
c) 14.26 ohm
d) 29.69 ohm
Answer: a

58. Batteries are generally connected in______
a) Series
b) Parallel
c) Either series or parallel
d) Neither series nor parallel
Answer: a

59. In a _________ circuit, the total resistance is greater than the largest resistance in the circuit.
a) Series
b) Parallel
c) Either series or parallel
d) Neither series nor parallel
Answer: a

60. In a ____________ circuit, the total resistance is smaller than the smallest resistance in the circuit.
a) Series
b) Parallel
c) Either series or parallel
d) Neither series nor parallel
Answer: b

61. Which is the most cost efficient connection?
a) Series
b) Parallel
c) Either series or parallel
d) Neither series nor parallel
Answer: a

62. Calculate the equivalent resistance between A and B.

a) 2 ohm
b) 4 ohm
c) 6 ohm
d) 8 ohm
Answer: b

63. Calculate the equivalent resistance between A and B.

a) 6.67 ohm
b) 46.67 ohm
c) 26.67 ohm
d) 10.67 ohm
Answer: a

64. Find the value of v if v1=20V and value of current source is 6A.

a) 10V
b) 12V
c) 14V
d) 16V
Answer: b

65. Calculate the current A.

a) 5A
b) 10A
c) 15A
d) 20A
Answer: c

66. Calculate the current across the 20 ohm resistor.

a) 20A
b) 1A
c) 0.67A
d) 0.33A
Answer: d

67. Calculate the value of I3, if I1= 2A and I2=3A.

a) -5A
b) 5A
c) 1A
d) -1A
Answer: a

68. Find the value of i2, i4 and i5 if i1=3A, i3=1A and i6=1A.

a) 2,-1,2
b) 4,-2,4
c) 2,1,2
d) 4,2,4
Answer: a

69. What is the value of current if a 50C charge flows in a conductor over a period of 5 seconds?
a) 5A
b) 10A
c) 15A
d) 20A
Answer: b

70. KCL deals with the conservation of?
a) Momentum
b) Mass
c) Potential Energy
d) Charge
Answer: d

71. KCL is applied at _________
a) Loop
b) Node
c) Both loop and node
d) Neither loop nor node
Answer: b

72. KCL can be applied for __________
a) Planar networks
b) Non-planar networks
c) Both planar and non-planar
d) Neither planar nor non-planar
Answer: c

73. What is the value of the current I?

a) 8A
b) 7A
c) 6A
d) 5A
Answer: a

74. Calculate the value of V1 and V2.

a) 4V, 6V
b) 5V, 6V
c) 6V, 7V
d) 7V, 8V
Answer: a

75. KVL deals with the conservation of?
a) Mass
b) Momentum
c) Charge
d) Energy
Answer: d

76. Calculate the voltage across the 10 ohm resistor.

a) 12V
b) 4V
c) 10V
d) 0V
Answer: b

77. Find the value of the currents I1 and I2.

a) 0.3, 0.1
b) -0.1, -0.3
c) -0.3, -0.1
d) 0.1, 0.2
Answer: d

78. The sum of the voltages over any closed loop is equal to __________
a) 0V
b) Infinity
c) 1V
d) 2V
Answer: a

79. What is the basic law that has to be followed in order to analyze the circuit?
a) Newton’s laws
b) Faraday’s laws
c) Ampere’s laws
d) Kirchhoff’s law
Answer: d

80. Every____________ is a ____________ but every __________ is not a __________
a) Mesh, loop, loop, mesh
b) Loop, mesh, mesh, loop
c) Loop, mesh, loop, mesh
d) Mesh, loop, mesh, loop
Answer: a

81. What is the voltage across the 5 ohm resistor if current source has current of 17/3 A?

a) 2.32V
b) 5.21V
c) 6.67V
d) 8.96V
Answer: b

82. Calculate VAB.

a) 3.5V
b) 12V
c) 9.5V
d) 6.5V
Answer: a

83. KVL is applied in ____________
a) Mesh analysis
b) Nodal analysis
c) Both mesh and nodal
d) Neither mesh nor nodal
Answer: a

84. Which of the following is not an expression power?
a) P=VI
b) P=I2R
c) P=V2/R
d) P=I/R
Answer d

85. Which of the following statements are true?
a) Power is proportional to voltage only
b) Power is proportional to current only
c) Power is neither proportional to voltage nor to the current
d) Power is proportional to both the voltage and current
Answer: d

86. A 250V bulb passes a current of 0.3A. Calculate the power in the lamp.
a) 75W
b) 50W
c) 25W
d) 90W
Answer: a

87. Kilowatt-hour(kWh) is a unit of?
a) Current
b) Power
c) Energy
d) Resistance
Answer: c

88. Calculate the power in the 20 ohm resistance.

a) 2000kW
b) 2kW
c) 200kW
d) 2W
Answer: b

89. A current of 5A flows in a resistor of 2 ohms. Calculate the energy dissipated in 300 seconds in the resistor.
a) 15kJ
b) 15000kJ
c) 1500J
d) 15J
Answer: a

90. Calculate the power across each 20 ohm resistance.

a) 1000W, 1000W
b) 500W, 500W
c) 1000kW, 1000kW
d) 500kW, 500kW
Answer: b

91. Calculate the power across each 10 ohm resistance.

a) 1000kW, 1000kW
b) 1kW, 1kW
c) 100W, 100W
d) 100kW, 100kW
View Answer

Answer: b

92. Calculate the work done in a resistor of 20 ohm carrying 5A of current in 3 hours.
a) 1.5J
b) 15J
c) 1.5kWh
d) 15kWh
Answer: c

93. The SI unit of power is?
a) kW(kilo-watt)
b) J/s(joules per second)
c) Ws(watt-second)
d) J/h(joules per hour
Answer: b

94. Which among the following is a unit for electrical energy?
a) V(volt)
b) kWh(kilowatt-hour)
c) Ohm
d) C(coloumb)
Answer: b

95. A bulb has a power of 200W. What is the energy dissipated by it in 5 minutes?
a) 60J
b) 1000J
c) 60kJ
d) 1kJ
Answer: c

96. Out of the following, which one is not a source of electrical energy?
a) Solar cell
b) Battery
c) Potentiometer
d) Generator
Answer: c

97. Calculate the energy dissipated by the circuit in 50 seconds.

a) 50kJ
b) 50J
c) 100j
d) 100kJ
Answer: a

98. Which among the following is an expression for energy?
a) V2It
b) V2Rt
c) V2t/R
d) V2t2/R
Answer: c

99. Calculate the energy in the 10 ohm resistance in 10 seconds.

a) 400J
b) 40kJ
c) 4000J
d) 4kJ
Answer: b

100. A battery converts___________
a) Electrical energy to chemical energy
b) Chemical energy to electrical energy
c) Mechanical energy to electrical energy
d) Chemical energy to mechanical energy
Answer: b

101. A current of 2A flows in a wire offering a resistance of 10ohm. Calculate the energy dissipated by the wire in 0.5 hours.
a) 72Wh
b) 72kJ
c) 7200J
d) 72kJh
Answer b

102. Calculate the energy in the 5 ohm resistor in 20 seconds.

a) 21.5kJ
b) 2.15kJ
c) 2.15J
d) 21.5J
Answer: a

103. Practically, if 10kJ of energy is supplied to a device, how much energy will the device give back?
a) Equal to10kJ
b) Less than 10kJ
c) More than 10kJ
d) Zero
Answer: b

104. Materials which easily allow the passage of electric current are known as ______
a) Insulators
b) Conductors
c) Dielectrics
d) Semi-conductors
Answer: b

105. A wire of length 2m and another wire of length 5m are made up of the same material and have the same area of cross section, which wire has higher resistance?
a) Both have equal resistance
b) The 2m wire has higher resistance
c) The 5m wire has higher resistance
d) The value of resistance cannot be determined from the given data
Answer: c

106. A wire having an area of cross section = 10sqm and another wire having an area of cross section= 15sqm, have the same length and are made up of the same material. Which wire has more resistance?
a) Both have equal resistance
b) The 10sqm wire has higher resistance
c) The 15sqm wire has higher resistance
d) The value of resistance cannot be determined from the given data
Answer: b

107. Which of the following statements are true with regard to resistance?
a) Resistance is directly proportional to a length of the wire
b) Resistance is directly proportional to an area of cross section of the wire
c) Resistance is inversely proportional to the length of the wire
d) Resistance is inversely proportional to the resistivity of the wire
Answer: a

108. A wire has the same resistance as the one given in the figure. Calculate its resistivity if the length of the wire is 10m and its area of cross section is 2m.

a) 16 ohm-metre
b) 8 ohm-metre
c) 16 kiloohm-metre
d) 8 kiloohm-metre
Answer: b

109. Which, among the following is a unit for resistivity?
a) ohm/metre
b) ohm/metre2
c) ohm-metre
d) ohm-metre2
Answer: c

110. What is the resistivity of Copper?
a) 1.59*10-8ohm-m
b) 2.7*10-8ohm-m
c) 7.3*10-8ohm-m
d) 5.35*10-8ohm-m
Answer: a

111. Calculate the ratio of the resistivity of 2 wires having the same length and same resistance with area of cross section 2m2 and 5m2 respectively.
a) 5:7
b) 2:7
c) 2:5
d) 7:5
Answer: c

112. Which of the following statements are true with regard to resistivity?
a) Resistance depends on the temperature
b) Resistance does not depend on the temperature
c) Resistivity depend on the length
d) Resistivity depend on area of cross section
Answer: a

113. The reciprocal of resistivity is________
a) Conductance
b) Resistance
c) Conductivity
d) Impedance
Answer: c

114. The resistance of pure metals ___________
a) Increases with an increase in temperature
b) Decreases with an increase in temperature
c) Remains the same with an increase in temperature
d) Becomes zero with an increase in temperature
Answer: a

115. The resistance of insulators __________
a) Increases with an increase in temperature
b) Decreases with an increase in temperature
c) Remains the same with an increase in temperature
d) Becomes zero with an increase in temperature
Answer: b

116. Which of the following statements are true about metals?
a) Metals have a positive temperature coefficient
b) Metals have a negative temperature coefficient
c) Metals have zero temperature coefficient
d) Metals have infinite temperature coefficient
Answer: a

117. Which of the following statements are true about insulators?
a) Insulators have a positive temperature coefficient
b) Insulators have a negative temperature coefficient
c) Insulators have zero temperature coefficient
d) Insulators have infinite temperature coefficient
Answer: b

118. What is the unit of temperature coefficient?
a) ohm/centigrade
b) ohm-centigrade
c) centigrade-1
d) centigrade
Answer: c

119. A copper coil has a resistance of 200 ohms when its mean temperature is 0 degree centigrade. Calculate the resistance of the coil when its mean temperature is 80 degree centigrade. Temperature coefficient of copper is 0.004041 centigrade-1
a) 264.65 ohm
b) 264.65 kilo-ohm
c) 286.65 ohm
d) 286.65 kilo-ohm
Answer: a

120. The temperature of a coil cannot be measured by which of the following methods?
a) Thermometer
b) Increase in resistance of the coil
c) Thermo-junctions embedded in the coil
d) Calorimeter
Answer: d

121. The rise or fall in resistance with the rise in temperature depends on ________
a) The property of the conductor material
b) The current in the metal
c) Property of material as well current in that material
d) Does not depend on any factor
Answer: a

122. If the temperature is increased in semi-conductors such that the resistance incessantly falls, it is termed as _______
a) Avalanche breakdown
b) Zener breakdown
c) Thermal runway
d) Avalanche runway
Answer: c

123. Materials having resistance almost equal to zero is _______
a) Semi-conductor
b) Conductor
c) Superconductors
d) Insulators
Answer: c