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Multiple Choice Questions
1. Which of the following is true for electrostatics?
a. 𝐸 = −∇𝑉
b. ∇ 2V = 0
c. Both (a) and (b)
d. None of these
2. According to Coulomb's Law, force between two point charges is
a. ∝ (distance)2
b. ∝ (distance)
c. (a) and (b)
d. None
3. The value of ε 0 the absolute permittivity is ________ pF/m.
a. 8.854
b. 8.854 × 10−12
c. 8.845 × 10−10
d. 8.854 × 10−10
4. Electric field intensity is related to force F and charge q as __________.
a. E=F/Q
b. E=Q/F
c. E=FQ
d. E=F.Q
5. Electric field intensity due to volume charge is given as
a. 𝐸 = −∇𝑉
𝑄
b. 𝐸 = 4𝜋∈𝑟 2
P
c. 𝐸 =
∫ 𝜌𝑣𝑑𝑣
4𝜋∈𝑟
∫ 𝜌𝑠𝑑𝑠
d. 𝐸 =
4𝜋∈𝑟
6. Electric flux density________medium.
a. Depends on
b. Independent of
c. Both (a) and (b)
d. None of these
7. Poisson's equation is given as
a. 𝐸 = −∇2 𝑉
𝜌𝑣
b. ∇2 𝑉 = − ∈
c. ∇2 𝑉=0
d. All
8. Electric potential V is given as
𝑄
a. 𝑉 = 4𝜋∈𝑟
b. V=−∇E
c. Both (a) and (b)
d. None
Page 1 of 12
9. Potential energy of a test charge, when moved from a lower potential point to a higher
potential point.
a. Remains the same
b. Increases
c. Decreases
d. Becomes zero
10. As per Gauss's Law, the total electric flux φ through a closed surface and the total charge
q enc by that surface are related as
a. ∅ = ∫ 𝐵𝑑𝑠
b. Q=∅
c. Both
d. None
11. Identify the configuration in figure 1 that is not a correct representation of I and H.
(a) fig. a (b) fig. b (c) fig. c (d) both fig. d and e
12. In equation B = 𝛁𝑿𝑨 , vector magnetic potential is
(a) B (b) A (c) Both (d) None
13. A charge of 12 C has velocity of 5ax + 2ay - 3az m/s. Determine F on the charge in the
field of (a) E=18ax,+5ay +10az V/m (b) B = 4ax + 4ay + 3az wb/m2.
(a) F = 254.27 N and 415.17 N (b) 154.17N and 315.17 N ( c) Both are possible (d) Nil
14. A rectangular coil is placed in a field of B = (2ax + ay) wb/m2. The coil is in y-z plane
and has d(a) Scalar quantity (b) Vector quantity (c) Both (d) None imensions of 2 m x 2
m. It carries a current of 1 A. Find the torque about the z-axis.
(a) 6ay
(b) (b) 6 az N-m
(c) (c) 4 az
(d) (d) 4 Az N-m
Page 2 of 12
15. Inductance of a toroid and solenoid are given respectively by
(a) 𝐿 =
𝜇𝑆𝑁 2
2𝜋𝑟
𝜇𝑆𝑁 2
(b) 𝐿 = 𝑙
(c) Either
(d) None
and 𝐿 =
and 𝐿 =
𝜇𝑆𝑁 2
𝑙
𝜇𝑆𝑁 2
2𝜋𝑟
16. Electric charge, electric potential, energy, temperature etc. are examples of
a)
Scalar quantity (b) Vector quantity (c) Both (d) None
17. Force, Electric field intensity are the examples of
(a)
18.
Scalar quantity (b) Vector quantity (c) Both (d) None
represents
(a) Scalar or dot product (b) Vector or Cross product (c) Both (d) None
19. Coulomb’s law gives
(a) Force between two charges (b)Energy between two charges
(c) both (d) None
20. Force per unit charge is
(a) Electric field intensity (b) Electric potential (c) both (d) None
(b)
None
21. Capacitance is
(a) Charge per unit area
(b) Charge per volts
(c) Charge/ length
(d) None
22. Lorentz force equation comprises __________ and __________ forces.
a.
b.
c.
d.
Electric, magnetic
Mechanical, chemical
Both (a) and (b)
None of these
23. Magnetic flux density is a relation of
a.
b.
c.
d.
Current and area
Area and its direction
Magnetic flux and area
None of these
Page 3 of 12
24. Magnetic flux density is analogous to
a. Magnetic induction
b. Electric field strength
c. Both (a) and (b)
d. Electric flux density
25. Total flux passing through a closed surface held in a magnetic field is
a. Infinity
b. Zero
c. Unity
d. None of these
26. Magnetic vector potential for volume current is expressed as
a. 𝐵 = ∇ × 𝐴
b. 𝐴 = ∇ × 𝐵
c. 𝐵 = ∇. 𝐴
d. 𝐴 = ∇. 𝐵
27. -----Can be obtained from vector magnetic potential .
a. Magnetic field intensity
b. Magnetic flux density
c. Both (a) and (b)
d. None of these
28. According to right hand thumb rule, thumb indicates
a. Flow of current
b. Non-uniform magnetic field
c. Both (a) and (b)
d. Magnetic field lines
29. Energy density W H is given as __________.
a. Energy per volume
b. Energy per area
c. Linear enenrgy
d. All of these
30. When two charges of +2C and -0.5C are brought in contact and then separated the
charges on each charge will be
a. Equal and same
b. Unequal and same
c. Equal and opposite
d. Unequal and opposite
31. Magnitude of dipole moment is given as
a. qd
b. q/d
c. d/q
d. None of these
32. If work done W mn is zero, then V N and V M are related as
a. VN + VM = 0
b. V N − V M = 0
c. 2V N + V M = 0
d. V N + 2V M = 0
Page 4 of 12
33. Charge distribution symmetry can be of .
a. Spherical type
b. Cylindrical type
c. Planar type
d. All of these
34. Curl of electrostatic field is
a. ∞
b. 1
c. 0
d. None of these
35. As per Stoke's Theorem, H the magnetic field intensity is
a. ∞
b. 1
c. 0
d. None of these
36. In the case of a linear material medium, which equation can be derived easily from
Gauss' law.
a. Poisson
b. Laplace
c. Both (a) and (b)
d. None of these
37. According to ampere’s law
a. Total electric flux is equal to electric charge
b. Total magnetic flux is equal to electric charge
c. Total magnetic flux is equal to current passing
d. None of these
38. Electric and magnetic fields are
a. Perpendicular to each other
b. Parallel to each other
c. Both (a) and (b)
d. None of these
39. Angular velocity has units of
a. Radians
b. Meter
c. Radians/meter
d. None of these
𝜀𝑜𝜀𝑟𝐴
40. Capacitance of parallel plate capacitor is given by 𝑑 where ε o represents
a)
b)
c)
d)
Permittivity
(b) Area
(c) Absolute permittivity
(d) None
Page 5 of 12
41. Energy stored in a capacitor is given by
1
(a) W=2 𝐶𝑉 2
(b) W=Q2/2C
(c) Both
(d) None.
42. F=qBXV represents the force exerted on a
(a) Charge q moving with velocity V in an electric field
(b) Charge q moving with velocity V in a magnetic field B
(c) Both
(d) None
43. When there is change in magnetic flux, emf is induced. This statement is
a.
b.
c.
d.
Faraday's First
Faraday's Second
Faraday's Third
Faraday's Fourth
44. The direction of emf induced is always such as to oppose the very reason producing the
emf. This is according to
a.
b.
c.
d.
Bio–Savart's
Lenz's
Ampere's
Faraday's
45. Biot–Savart's Law is expressed mathematically as
a. 𝐻
b. 𝐵 ∝ ∫ 𝐼𝑑𝑙𝑠𝑖𝑛𝜃/𝑟 2
c. ∫ 𝐻𝑑𝑙 = 𝐼𝑒𝑛𝑐
d. ∫ 𝐻𝑑𝑙 = ∫(∇XH)ds
46. Biot–Savart's Law can be applied to current-carrying conductors of
a. Large length
b. Medium length
c. Small length
d. Very small length
Page 6 of 12
47. The magnitude of the emf induced is directly proportional to rate of change of flux. This
is put forth by
a. Bio–Savart's
b. Faraday’s I law
c. Ampere's
d. Faraday’s II law
48. According to Ampere's Circuital Law, field intensity at a point at distance R from a
very long straight filament conductor-carrying current I is given as
a. ∫ 𝐻𝑑𝑙 = 𝐼𝑒𝑛𝑐
b. ∫ 𝐽𝑑𝑠 = 𝐼
c. Both (a) and (b)
d. None
49. Ampere's Circuital Law and which of the following law in electrostatics are analogous
a. Lenz's
b. Gauss's
c. Biot–Savart's
d. Faraday's
50. Ampere's Circuital Law can be applied __________ the conductor.
a. Inside
b. Outside
c. Both (a) and (b)
d. None of these
51. In the above expression, r represents
(a) Distance between charge and point
(b) Distance between current element and the point under consideration
(c) Distance between two charges
(d) None
52. According to Maxwell's first equation in integral form
a.
b.
c.
d.
∇. 𝐷 = 𝜌𝑣
∫ 𝐷𝑑𝑠 = ∫(∇. D)dv
∫ 𝐻𝑑𝑙 = ∫(∇XH)ds
∇XH = Jc + Jd
52. According to Maxwell's first equation in differential form gives
a.
b.
c.
d.
∇. 𝐷 = 𝜌𝑣
∫ 𝐷𝑑𝑠 = ∫(∇. D)dv
∫ 𝐻𝑑𝑙 = ∫(∇XH)ds
∇XH = Jc + Jd
Page 7 of 12
53. According to Maxwell's second equation in differential form gives
a. ∇. 𝐷 = 𝜌𝑣
b. ∫ 𝐷𝑑𝑠 = ∫(∇. D)dv
c. ∫ 𝐻𝑑𝑙 = ∫(∇XH)ds
d. ∇XH = Jc + Jd
54. According to Maxwell's second equation in integral form gives
a. ∇. 𝐷 = 𝜌𝑣
b. ∫ 𝐷𝑑𝑠 = ∫(∇. D)dv
c. ∫ 𝐻𝑑𝑙 = ∫(∇XH)ds
d. ∇XH = Jc + Jd
55. Maxwell's third equation in differential form gives
a. ∇. 𝐷 = 𝜌𝑣
b. ∫ 𝐸𝑑𝑙 = ∫(∇XE)ds
c. ∫ 𝐻𝑑𝑙 = ∫(∇XH)ds
d. ∇XE = − ∂B/ ∂t
56. Maxwell's third equation in integal form gives
a. ∇. 𝐷 = 𝜌𝑣
b. ∫ 𝐸𝑑𝑙 = ∫(∇XE)ds
c. ∫ 𝐻𝑑𝑙 = ∫(∇XH)ds
d. ∇XE = − ∂B/ ∂t
57. Maxwell's fourth equation in differential form gives
a. ∇. 𝐵 = 0
b. ∫ 𝐵𝑑𝑠 = 0
c. ∫ 𝐻𝑑𝑙 = ∫(∇XH)ds
d. ∇XE = − ∂B/ ∂t
58. Maxwell's fourth equation in integral form gives
a. ∇. 𝐵 = 0
b. ∫ 𝐵𝑑𝑠 = 0
c. ∫ 𝐻𝑑𝑙 = ∫(∇XH)ds
d. ∇XE = − ∂B/ ∂t
59. Maxwell's equations involve
a. Charge density
b. Current density
c. Magnetic intensity
d. All of these
60. Maxwell's equations are based on __________ law(s).
a. Faraday's
b. Gauss's
c. Ampere's
d. All of these
Page 8 of 12
61. Maxwell's equations in __________ form give information at points of discontinuity in
electromagnetic fields.
a. Differential
b. Integral
c. Algebraic
d. None of these
62. According to Ampere's Circuital Law
a. ∫ 𝐻𝑑𝑙 = 𝐼
b. ∫ 𝐻𝑑𝑙 = 𝐼𝑒𝑛𝑐
c. ∫ 𝐻𝑑𝑙 = ∫(∇XH)ds
d. ∇XE = − ∂B/ ∂t
63. Steady magnetic fields are governed by
a. Biot–Savart's law
b. Ampere's Circuital law
c. Both (a) and (b)
d. None of these
64. Wave speed in terms of frequency f and wavelength λ is expressed as.
a. f/λ
b. λ/f
c. λ f
d. (λ + f)
65. For a lossy dielectric medium,
a. σ = 0
b. σ ≠ 0
c. None of these
d. Cannot say
66. In the case of a perfect dielectric medium conductivity of wave is
a. More than 100%
b. Approaches 100%
c. Less than 100%
d. None of these
67. Phase velocity is given as
a. 𝑉 = 𝜆𝑓
b. β/ω
c. both (a) and (b)
d. None of these
68. For a good conductor
a. 𝜔𝜀 ≥ 𝜎
b. 𝜔𝜀 ≤ 𝜎
c. 𝜔𝜀 == 𝜎
d. None
69. For a good dielectric medium
a. 𝜔𝜀 ≥ 𝜎
b. 𝜔𝜀 ≤ 𝜎
c. 𝜔𝜀 == 𝜎
d. None
Page 9 of 12
70. In good conductors, rate of attenuation is
a. Small
b. Large
c. Infinity
d. Zero
71. Poynting Vector is obtained as
a. 𝑃 = 𝐸 × 𝐻
b. 𝑆 = 𝐸 × 𝐻
c. 𝐸 = 𝑃 × 𝐻
d. 𝐻 = 𝐸 × 𝑃
72. Power density is
a. Power delivered
b. Power /area
c. Both (a) and (b)
d. None of these
73. Reflection coefficient Γ is
a. ≥100
b. = 10
c. ≤ 1
d. None of these
74. As referred to the waves, correct equation is
a. (1 + Γ) = τ
b. (1 + τ) = Γ
c. (1 + Γ) τ = 0
d. (1 + τ)Γ = 0
75. Standing wave consists of two travelling waves of ____________ amplitudes and
_____________ is direction.
a. Unequal, same
b. Unequal, opposite
c. Equal, same
d. Equal, opposite
76. Standing wave ratio is given as
1+𝜏
a. 𝑆𝑊𝑅 = 1−𝜏
1−𝜏
b. 𝑆𝑊𝑅 = 1+𝜏
c. None
d. Both
77. SWR ranges from ______.
a. 0 to 1
b. 1 to 10
c. 10 to 100
d. 1 to ∞
Page 10 of 12
78. Waves are used in __________.
a. TV
b. Radio
c. Radar
d. All of these
79. Curl of magnetic field intensity is
(a) Current density
(b) Magnetic field intensity
Page 11 of 12
(c) Current (d) None
Answers for the Multiple Choice Questions
1. (c)
2. (d)
3. (b)
4. (a)
5. (c)
6. (a)
7. (b)
8. (c)
9. (b)
10. (c)
11. (c)
12. (a)
13. (a)
14. (d)
15. (a)
16. (a)
17. (b)
18. (a)
19. (a)
20. (a)
21. (b)
22. (A)
23. (c)
24. (d)
25. (b)
26. (a)
27. (c)
28. (d)
29. (a)
30. (a)
31. (a)
32. (a)
33. (d)
34. (c)
35. (c)
36. (c)
37. (c)
38. (a)
39. (d)
40. (c)
41. (c)
42. (b)
43. (a)
44. (b)
45. (b)
46. (a)
47. (d)
48. (a)
49. (b)
50. (b)
51. (b)
52. (b)
53. (a)
54. (d)
55. (c)
56. (d)
57. (b)
58. (a)
59. (b)
60. (d)
Page 12 of 12
61. (d)
62. (a)
63. (b)
64. (c)
65. (c)
66. (b)
67. (b)
68. (a)
69. (b)
70. (a)
71. (b)
72. (b)
73. (b)
74. (c)
75. (b)
76. (d)
77. (a)
78. (a)
79. (d)
80. (a)