75+ Electromagnetism MCQ of Basic Electrical Engineering
1. What is the magnetic field outside a solenoid?
a) Infinity
b) Half the value of the field inside
c) Double the value of the field inside
d) Zero
Answer: d
2. Which, among the following qualities, is not affected by the magnetic field?
a) Moving charge
b) Change in magnetic flux
c) Current flowing in a conductor
d) Stationary charge
Answer: d
3. When a charged particle moves at right angles to the magnetic field, the variable quantity is?
a) Momentum
b) Speed
c) Energy
d) Moment of inertia
Answer: a
4. If the flow of electric current is parallel to the magnetic field, the force will be ______
a) Zero
b) Infinity
c) Maximum
d) Half the original value
Answer: a
5. The ratio of magnetic force to electric force on a charged particle getting undeflected in a field is?
a) 1
b) 0
c) 2
d) 4
Answer: a
6. What is the strength of magnetic field known as ________
a) Flux
b) Density
c) Magnetic strength
d) Magnetic flux density
Answer: d
These are 50+ Electromagnetism MCQ
7. Weakest force in nature is?
a) Electric force
b) Gravitational force
c) Weak force
d) Magnetic force
Answer: b
8. How can a magnetic field be produced?
a) Using a permanent magnet
b) Electric current
c) Using a temporary magnet
d) Using a permanent magnet or electric current
Answer: d
9. Can we see magnetic flux lines?
a) Yes
b) No
c) Depends on the strength of the field
d) Only when the field strength is very large
Answer: b
10. Magnetic Field lines move from _______
a) North to south
b) South to north
c) West to east
d) East to west
Answer: a
11. Field lines move from __________
a) North to south
b) South to north
c) West to east
d) East to west
Answer: a
12. Magnetic field lines ___________ at the north pole.
a) Emerge
b) Converge
c) Neither emerge nor converge
d) Either emerge or converge
Answer: a
13. Magnetic field lines ___________ at the south pole.
a) Emerge
b) Converge
c) Neither emerge nor converge
d) Either emerge or converge
Answer: b
14. Which of the following is used to determine the direction of magnetic field in a current carrying conductor?
a) Left hand thumb rule
b) Right hand thumb rule
c) Right hand palm rule
d) Left hand palm rule
Answer: b
15. According to Flemming’s left hand rule, the index finger denotes?
a) Direction of magnetic field
b) Direction of current
c) Direction of force
d) Direction of force as well as current
Answer: a
16. According to Flemming’s left hand rule, the middle finger denotes?
a) Direction of magnetic field
b) Direction of current
c) Direction of force
d) Direction of force as well as current
Answer: b
17. According to Flemming’s left hand rule, the thumb denotes?
a) Direction of magnetic field
b) Direction of current
c) Direction of force
d) Direction of force as well as current
Answer: c
18. The relation between the direction of force and the direction of magnetic field is _________
a) Same direction
b) Opposite direction
c) Perpendicular
d) Unrelated
Answer: c
19. The relation between the direction of current and the direction of magnetic field is ________
a) Same direction
b) Opposite direction
c) Perpendicular
d) Unrelated
Answer: c
20. The relation between the direction of current and the direction of the force is _________
a) Same direction
b) Opposite direction
c) Perpendicular
d) Unrelated
Answer: c
21. Magnetic field lines seek the path of __________ resistance.
a) Maximum
b) Minimum
c) Infinite
d) Zero
Answer: b
22. Magnetic field lines form _________ loops from pole to pole.
a) Open
b) Closed
c) Branched
d) Either closed or branched
Answer: b
23. Do magnetic flux lines intersect?
a) Yes
b) No
c) Depends on the situation
d) Cannot be determined
Answer: b
24. Inside the magnet, field lines travel from?
a) North to south
b) South to north
c) West to east
d) East to west
Answer: b
25. Lines of magnetic flux which are parallel and in the same direction __________ each other.
a) Attract
b) Repel
c) Intersect
d) Cancel
Answer: b
26. More the number of magnetic flux lines _______ is the force of the magnet.
a) Greater
b) Lesser
c) Either greater or lesser
d) Neither greater nor lesser
Answer: a
27. Magnetic field is strong when____________
a) magnetic field lines are closer
b) magnetic field lines are farther
c) magnetic field lines are longer
d) magnetic field lines are thicker
Answer: a
28. The force existing between two infinite parallel conductors is inversely proportional to ________
a) Radius of the conductors
b) Current in one of the conductors
c) The product of the current in the two conductors
d) The distance between the two conductors
Answer: d
29. When the distance of operation between the two conductors increases, what happens to the force between the two conductors?
a) Increases
b) Decreases
c) Remains the same
d) Becomes zero
Answer: b
30. Magnetic field at a point d distance away from long wire due to electric current i in it is ____________
a) µ0i/2r
b) µ0i/r
c) µ0i/2πr
d) µ0i/πr
Answer: c
31. The force per unit length existing between two infinite parallel conductors is given by ___________
a) µ0i1i2/2πd
b) µ0i1i2/2d
c) µ0i1/2πdi2
d) µ0i1i2/d
Answer: a
32. If the radius of the current carrying conductor increases, what is the effect on the force?
a) increases
b) decreases
c) remain same
d) become zero
Answer: c
33. If current of conductor increases, what is the effect on the force?
a) increases
b) decreases
c) remain same
d) become zero
Answer: a
34. If length of current carrying conductor increases, what is the effect on the force?
a) increases
b) decreases
c) remain same
d) become zero
Answer: a
35. The magnetic field strength of a solenoid can be increased by inserting which of the following materials as the core?
a) Copper
b) Silver
c) Iron
d) Aluminium
Answer: c
36. If a coil is wound around a steel core and electric current is passed through the coil, the steel core acts as a?
a) Electromagnet
b) Permanent magnet
c) Neither electromagnet nor permanent magnet
d) Either electromagnet or permanent magnet
Answer: b
For more visit PROGIES homepage
37. What is the formula for the magnetic field due to a solenoid?
a) μnI
b) μn2
c) μNI
d) μN2I2
Answer: a
38. What happens to the magnetic field in the solenoid when the number of turns increases?
a) Increases
b) Decreases
c) Remains constant
d) Becomes zero
Answer: a
39. What happens to the magnetic field in the solenoid when the current increases?
a) Increases
b) Decreases
c) Remains constant
d) Becomes zero
Answer: a
40. What happens to the magnetic field in the solenoid when the length of the solenoid increases?
a) Increases
b) Decreases
c) Remains constant
d) Becomes zero
Answer: b
41. The current in a solenoid is 30A, the number of turns per unit length is 500 turns per metre. Calculate the magnetic field if the core is air.
a) 18.84T
b) 18.84mT
c) 1.84T
d) 1.84mT
Answer: b
These are 50+ Electromagnetism MCQ
42. The magnetic field of the solenoid is 18.84mT, the number of turns per unit length is 500 turns per metre. Calculate the current if the core is air.
a) 300A
b) 30A
c) 3A
d) 300mA
Answer: b
43. The magnetic field of the solenoid is 18.84mT, the current is 30A. Calculate the number of turns per unit length if the core is air.
a) 1500 turns/m
b) 1000 turns/m
c) 500 turns /m
d) 2000 turns/m
Answer: c
44. What is the expression for force in a current carrying conductor?
a) F=K/r2
b) F=Kq/r2
c) F=Kq1q2/r2
d) F=Kq1q2/r
Answer: c
45. Force in a conductor is__________ to the product of the charges.
a) Directly proportional
b) Inversely proportional
c) Not related
d) Cannot be determined
Answer: a
46. Force in a conductor is __________ to the square of the distance between the charges.
a) Directly proportional
b) Inversely proportional
c) Not related
d) Cannot be determined
Answer: b
47. Calculate the force between two charges having magnitude 3nC and 2nC separated by a distance of 2micro m.
a) 13.5N
b) 13.5kN
c) 1.35N
d) 1.35kN
Answer: b
48. If the flow of electric current is parallel to the magnetic field, the force will be?
a) Zero
b) Infinity
c) Maximum
d) Half the original value
Answer: a
49. The ratio of magnetic force to electric force on a charged particle getting undeflected in a field is ______
a) 1
b) 0
c) 2
d) 4
Answer: a
50. Weakest force in nature is __________
a) Electric force
b) Gravitational force
c) Weak force
d) Magnetic force
Answer: a
These are 50+ Electromagnetism MCQ
51. The relation between the direction of force and the direction of magnetic field is __________
a) Same direction
b) Opposite direction
c) Perpendicular
d) Unrelated
Answer: c
52. The relation between the direction of current and the direction of the force is ________
a) Same direction
b) Opposite direction
c) Perpendicular
d) Unrelated
Answer: c
53. Which among the following, is the correct expression for force in a current carrying conductor if magnetic field is perpendicular to it?
a) F=Bi
b) F=B2il
c) F=Bil
d) F=Bl2
Answer: c
54. When the current in the current carrying conductor increases, what happens to the force in the conductor which is at right angles to the magnetic field?
a) Increases
b) Decreases
c) Remains the same
d) Becomes zero
Answer: a
These are 50+ Electromagnetism MCQ
55. When the length of the conductor in the current carrying conductor increases, what happens to the force in the conductor which is at right angles to the magnetic field?
a) Increases
b) Decreases
c) Remains the same
d) Becomes zero
Answer: a
56. When the magnetic field intensity in the current carrying conductor increases, what happens to the force in the conductor which is at right angles to the magnetic field?
a) Increases
b) Decreases
c) Remains the same
d) Becomes zero
Answer: a
57. The unit for force in a current carrying conductor is _________
a) Tesla*Ampere*metre
b) Tesla
c) Ampere/metre
d) Ampere*metre
Answer: a
58. If net force is zero on a particle in magnetic field what is relation between velocity and magnetic field?
a) v=E*B
b) v=E/B
c) v=B/E
d) v=1/(E*B)
Answer: b
59. If the intensity of the magnetic field is 100T, the length of the conductor is 10m and the magnitude of force perpendicular to the magnetic field is 10kN,calculate the current in the conductor.
a) 100 A
b) 100 mA
c) 10 A
d) 10 mA
Answer: c
These are 50+ Electromagnetism MCQ
60. If the intensity of the magnetic field perpendicular to current carrying conductor is 100T, the length of the conductor is 3m and the current in the conductor is 10A, calculate the magnitude of force perpendicular to the electric field.
a) 300N
b) 30N
c) 30kN
d) 3kN
Answer: d
61. Force in current carrying conductor placed in magnetic field is ___________ of il and B.
a) dot product
b) scalar product
c) cross product
d) vector addition
Answer: c
62. An E.M.F. can be induced by _________
a) Change in the magnetic field only
b) Change in the area of cross section only
c) Change in angle between magnetic field and area only
d) Change in the magnetic field, area or angle between them
Answer: d
63. What happens to the current in a coil while accelerating a magnet inside it?
a) Increases
b) Decreases
c) Remains constant
d) Reverses
Answer: a
64. What is the consequence of motor effect?
a) Current
b) Voltage
c) Electromagnetic induction
d) EMF
Answer: c
65. The total number of magnetic field lines passing through an area is termed as?
a) Voltage
b) EMF
c) Magnetic flux
d) Magnetic flux density
Answer: c
66. The formula for induced emf if magnetic field, length and velocity of conductor all are mutually perpendicular is __________
a) emf=B2l
b) emf=Bil
c) emf=Blv
d) emf=B2v
Answer: c
These are 50+ Electromagnetism MCQ
67. If a conductor 0.2m long moves with a velocity of 0.3m/s in a magnetic field of 5T, calculate the emf induced if magnetic field, velocity and length of conductor are mutually perpendicular to each other.
a) 0.3V
b) 0.03V
c) 30V
d) 3V
Answer: a
These are 50+ Electromagnetism MCQ
68. Find the length of a conductor which is moving with a velocity 0.4m/s in a magnetic field of 8T, inducing an emf of 20V if magnetic field, velocity and length of conductor are mutually perpendicular to each other.
a) 50m
b) 5m
c) 6.25m
d) 0.5m
Answer: c
69. Find the strength of the magnetic field in a conductor 0.5m long moving with a velocity of 10m/s, inducing an emf of 20V if magnetic field, velocity and length of conductor are mutually perpendicular to each other.
a) 1T
b) 2T
c) 3T
d) 4T
Answer: d
70. What does emf stand for?
a) Electronic magnetic force
b) Electromotive force
c) Electromagnetic force
d) Electromated force
Answer: b
71. What is emf?
a) Force
b) Voltage
c) Current
d) Flux
Answer: b
72. According to Faraday’s laws of electromagnetic induction, an emf is induced in a conductor whenever?
a) The conductor is perpendicular to the magnetic field
b) Lies in the magnetic field
c) Cuts magnetic lines of flux
d) Moves parallel to the magnetic field
Answer: c
73. Direction of induced emf is determined by __________
a) Fleming’s left hand rule
b) Fleming’s right hand rule
c) Faraday’s law
d) Right hand thumb rule
Answer: b
74. “The direction of an induced e.m.f. is always such that it tends to set up a current opposing the motion or the change of flux responsible for inducing that e.m.f.”, this is the statement for?
a) Fleming’s left hand rule
b) Fleming’s right hand rule
c) Faraday’s law
d) Lenz’s law
Answer: d
75. According to Fleming’s right hand rule, the thumb points towards?
a) Current
b) E.M.F.
c) Motion of the conductor
d) Magnetic flux
Answer: c
76. According to Fleming’s right hand rule, the index finger points towards?
a) Current
b) E.M.F.
c) Motion of the conductor
d) Magnetic flux
Answer: d
77. According to Fleming’s right hand rule, the middle finger points towards?
a) Current
b) E.M.F.
c) Motion of the conductor
d) Magnetic flux
Answer: b
78. The relation between the direction of induced emf and the direction of motion of the conductor is?
a) Parallel
b) Equal
c) Not related
d) Perpendicular
Answer: d
79. The relation between the direction of induced emf and the direction of magnetic flux is _______
a) Parallel
b) Equal
c) Not related
d) Perpendicular
Answer: d
80. The relation between the direction of magnetic flux and the direction of motion of the conductor is _______
a) Parallel
b) Equal
c) Not related
d) Perpendicular
Answer: d
Check more here : https://progies.in/100-current-electricity-questions
50+ Electromagnetism MCQ.
Check out more ……..