1. Maxwell's equations in __________ form give unformation at points
of discontinuity in electromagnetic fields.
Correct : B. Integral
2. Another boundary condition using Maxwell's equations is given as
__________.
Correct : D. Htan '1'− Htan '2' = Js
3. At the point of discontinuity, __________ component of magnetic flux
density is continuous.
Correct : B. Normal
4. For those surfaces where surface charge density is __________ normal component of electric flux density is continuous.
Correct : C. Zero
5. Waves are used in __________.
Correct : D. All of these
6. Displacement current density ____________ current passing
through a capacitor.
Correct : B. Does not represent
7. Line integral of an electric field around a closed path is __________.
Correct : C. zero
8. __________ are caused by accelerated charges
Correct : C. Both (a) and (b)
9. At the Brewster angle, polarization ______________.
Correct : A. Cannot be reflected
10. Wave number has units of____________.
Correct : C. Radians/meter
11. Wave speed in terms of frequency f and wavelength λ is expressed as _________.
Correct : C. λ f
12. For a lossy dielectric medium, ____________.
Correct : B. σ ≠ 0
13. Wave attenuation is given as ______________.
Correct : D. e−αx
14. In the case of a perfect dielectric medium, phase constant
______________ as conductivity increases.
Correct : A. Increases
15. Phase velocity is given as _________.
Correct : C. β/ω
16. In good conductors, rate of attenuation is __________.
Correct : C. Infinity
17. Power density has _________________.
Correct : C. Both (a) and (b)
18. Reflection coefficient Γ is __________.
Correct : C. ≤ 1
19. Which of the following expressions is correct?
Correct : A. (1 + Γ) = τ
20. Standing wave consists of two travelling waves of ____________ amplitudes and _____________ is direction.
Correct : D. Equal, opposite
21. SNR ranges from ______.
Correct : D. 1 to ∞
22. The Smith chart is a ________ dimensional representation of
complex impedances with respect to coordinates.
Correct : C. Four
23. In a _________ transmission line, the reflection coefficient domain is
a circle of unitary radius.
Correct : B. Lossless
24. The Smith chart represents a family of circles obtained by varying
normalized resistance in the range of __________.
Correct : C. 0 to ∞
25. A family of arcs is obtained in the Smith chart by varying normalized reactance in a range of __________.
Correct : D. −∞ to ∞
26. Smith charts depict a wide impedance range of transmitter for _______VSWR.
Correct : B. High
27. A cable or a wire is considered as a transmission line if its length is _________of the wavelength of the signal travelling through it.
Correct : A. Greater than 1/10
28. Transmission lines facilitate _________propagation of energy.
Correct : A. Guided
29. A transmission line is specified in terms of _________.
Correct : C. R, G, L,C
30. In planar transmission lines, C = _________.
Correct : C. b/d
31. In a microstrip line, there is _________metal strip over the substrate.
Correct : A. A thin
32. In a fully lossless line, σ = _________.
Correct : C. ∞
33. In a distortionless line, attenuation constant α is frequency
_________.
Correct : B. Independent
34. A distortion less line has _________.
Correct : D. All of these
35. Voltage reflection coefficient is the ratio of _________ wave to
_______ wave.
Correct : B. Reflected, incident
36. ________ are very efficient in a frequency range of 3-300 GHz.
Correct : B. Wave guides
37. Wave guides ________ in DC applications.
Correct : B. Cannot be used
38. Wave guides are a type of _________ filter.
Correct : D. High pass
39. For lossless wave guides, σc ________and σ ______
Correct : A. ∞, 0
40. In the TM mode, Ez _____ and Hz = ________.
Correct : D. None of these
41. In the TEM mode, Ez ______ and Hz =_______
Correct : A. 0, 0
42. Below the cut-off frequency, there is_______________.
Correct : A. Attenuation
43. Cut-off wavelength λc in the TE10 mode is ____________.
Correct : B. 2a
44. _______ velocity is the one at which loss of constant phase propagates
down the guide.
Correct : B. Phase
45. Information or energy through the wave guide travels at _______
velocity.
Correct : C. Group
46. _______velocity is that whose resultant repeated reflected waves
travel down the guide.
Correct : C. Group
47. ________ vector is needed to determine power flow in wave guides.
Correct : B. Average Poynting
48. Surface current density K on wave guide walls for ______ is given as
Correct : C. Both (a) and (b)
49. At _______ frequencies, RLC resonant circuits are replaced by
electromagnetic cavity resonators.
Correct : C. High
50. Resonator cavities are used in _______.
Correct : D. All of these
51. Cavity is a rectangular wave guide _______.
Correct : B. Shorted at both ends
52. Antenna tuning is done by changing its___________.
Correct : C. Both (a) and (b)
53. Resonant frequency of an antenna depends upon its___________.
Correct : B. Electrical length
54. Impedance of an antenna is matched to feed___________.
Correct : C. Both (a) and (b)
55. In low-power applications, ideal SWR is___________.
Correct : A. 1:1
56. Which of the following is a low-gain antenna?
Correct : B. Wi-Fi antenna
57. In the case of an ideal isotropic antenna, the geometric radiation
pattern is___________.
Correct : B. Sphere
58. Antenna gain is minimum at radiation pattern___________.
Correct : A. Side lobes
59. Elliptical polarization can be of___________.
Correct : C. Either (a) or (b)
60. Transmitters used on vehicles are__________ polarized.
Correct : B. Circularly
61. Antenna bandwidth can be increased by using__________.
Correct : D. All of these
62. Antenna array is__________.
Correct : C. Either (a) or (b)
63. Array factor depends upon__________.
Correct : D. All of these
64. If antenna directivity and antenna gain are equal, then antenna
efficiency is __________%.
Correct : D. 100
65. If antenna array elemental spacing is large, then directivity will
be__________.
Correct : B. More
66. On the basis of the radiation pattern, an antenna array is__________.
Correct : C. Either (a) or (b)
67. In__________array, radiation is perpendicular to array orientation.
Correct : A. Broadside
68. In__________array, radiation is in the same direction as the array
orientation.
Correct : D. Cannot say
69. A large aperture means antenna gain will be__________.
Correct : B. Small
70. A short dipole antenna is__________.
Correct : C. Centre-fed
71. The force between two charges is 120 N. if the distance between the
charge is doubled, the force will be
Correct : B. 30 N
72. The electric field intensity at a point situated at 4 meters away from a point charge 200 N/C. if the distance is reduced to 2 meters, the field intensity will be.
Correct : C. 800 N/C
73. A hole of radius b (b < a) is now drilled along the length of the wire at a distance d from the center of the wire as shown below. The magnetic field inside the hole is
Correct : C. uniform and depends on both b and d
74. The line of force due to charged particles are always
Correct : B. Always curve
75. The electric field at a point situated as a distance d from straight
charged conductor is
Correct : B. Inversely proportional to d
76. The direction of electric field due to +0 positive charge is
Correct : A. Away from the charge
77. A field line and equipotential surface are
Correct : A. Always parallel
78. The ability of charged bodies to exert force on any another is
attributed to the existence of
Correct : C. Neutrons
79. A capacitor stored 0.24 coulombs at 10 volts ,its capacitance is
Correct : A. 0.024F
80. For making a capacitor , it is better to select a dielectric having
Correct : B. High permittivity
81. The units of capacitance are
Correct : B. Coulombs/volt
82. If three 15 uf capacitors are connected in series , the net capacitance
is
Correct : A. 5uf
83. A dielectric material must be
Correct : B. Insulator
84. An electrolytic capacitor can be used for
Correct : A. D.C. only
85. The capacitance of a capacitor is not affected by
Correct : C. Thickness of plates
86. Which of the following is not a vector?
Correct : A. Linear momentum
87. Two plates of parallel plate capacitor after being charged from a constant voltage source are separated apart by means of insulated handles, then the
Correct : B. Voltage across the plates decreases
88. If A.C. voltage is applied to capacititve circuit , th alternating current
can flow in the circuit because
Correct : A. Varying voltage produces the charging and discharging currents
89. Voltage applied across a ceramic dielectric produces an electrolytic field 100 times greater than air. What will be the value of dielectric constant?
Correct : B. 100
90. Which of the following statements is correct?
Correct : B. Electrolytic capacitor must be connected in the correct polarity
91. The dissipation factor of good dielectric is of the order of
Correct : A. 0.0002
92. “ the total electric flux through any closed surface surrounding
charges is equal to the amount of charge enclosed “.
Correct : B. Gauss’s law
93. Which of the following statement is true?
Correct : B. The current in the discharging capacitor grows exponentially
94. Which of the following expression is correct for electric field strength?
Correct : A. E = D/E
95. In a capacitor the electric charge is stored in
Correct : C. Ceramics
96. Which of the following capacitors will have the least variation?
Correct : C. Silver plated mica capacitor
97. Which of the following capacitor has relatively shorter shelf life?
Correct : B. Electrolytic capacitor
98. The sparking between two electrical contacts can be reduced by
inserting a
Correct : A. Capacitor in parallel with contacts
99. In the case of lossy capacitor, its series equivalent resistance value will be