1. In forward-bias portion of the thyristor’s V-I characteristics, the number of stable operating regions is
2. The dv/dt effect in SCR can result in
3. The Snubber circuit is used in thyristor circuits for
4. A UJT has
5. When UJT is used for triggering an SCR, the waveshape of the signal obtained from UJT circuit is
6. A power chopper converts
7. Which of the following memory uses one transistor and one capacitor as basic memory unit ?
8. Temperature variation is a/an
9. Boolean algebra is also known as
10. 2’s complement of the number of 1010101 is
11. A light sensitive device that converts drawing, printed text or other images into digital form is
12. First generation of computer was based on which technology ?
13. An error is also known as
14. Permanent magnets are normally made of
15. The unit of retentivity is
16. The rate of rise of current through an inductive coil is maximum
17. For audio frequency applications, the popular oscillator used is
18. A diode (p-n junction) when reverse biased act as
19. An Op-Amplifier Comparator circuit employs
20. Which of the following cannot actually move
21. In RC series circuit total voltage is 10 V and voltage across resistor is 6 V, then what is voltage across capacitor ?
22. In RLC parallel circuit, current through inductor is more than current through capacitor, then what is the power factor of the circuit ?
23. A Delta connected capacitor bank is preferred over a Star connected bank, to ensure
24.The Superposition Theorem is obeyed by
25. The symbol used for representing independent sources is
26. What should be the minimum depth (in metre) of cable trench to dug for laying of 1.1 kV ?
27.The hydel power plant of run-off river type should be provided with pondage so that the
28. If the fault current is 2000 A, the relay setting is 50% and CT ratio is 400:5,then plug setting multiplier will be
29. The number of strands of ACSR conductor for 4-layers transmission line is
30. In a 3-layer ACSR conductor, if diameter of each strand is d, then total diameter of conductor will be
31. The emf induced in a conductor rotating in a bipolar field is
32. Neglecting all losses, how is the developed torque (T) of a dc separately excitedmotor, operating under constant terminal voltage, related to its output power (P) ?
33. Pole shoe of a dc machine is laminated for the purpose of
34.Lap winding is preferred for which type of machines ?
35. Demagnetization effects which of the following ?
36. Which of the following is/are effects of armature reaction ?
37. The metric system is called
38. Which of the quantity consists of SI unit as Candela ?
39. Hysteresis in an instrument means
40. The chemical effect of the current is used in
41.The most suitable primary standard for frequency is
42. Substances having permeability less than the permeability of free space, are known as
43.De-guassing is the process of
44.Bohr magneton is unit of
45. Two different isotopes of an element have different
46.Which of the following material is commonly used for making magnetic recording tape ?
47. What is the angle between the pole and stay ?
48.How many earth connections are required for the motor frame as per the IE Rule-61 ?
49. How is the ballast resistance connected with the choke ?
50. What is the specification of GI earth plate ?
51. Which type of cable does not require bedding ?
52.What is the maximum distance between the two successive cleats ?
53. Spot welding is used to weld metal pieces whose thickness
54.A low frequency supply is given to the single phase AC system for track electrification because
55. Which among the following is mechanical braking ?
56.Three phase induction motor is not suitable for traction purpose because
57. The normal voltage used in directional heating is
58. In an arc furnace, the choke is provided to
59. If rated dc voltage is applied instead of ac to the primary of a transformer
60.A transformer with an output voltage of 4200 V is supplied at 230 V. If the secondary has 2100 turns, calculate the no. of primary turns.
61. The hot resistance of the filament of a bulb is higher than the cold resistance because the temperature coefficient of the filament is
62. A single phase A.C. voltage source has 200 V rms and a system connected consumes an active power of 300 W. What is the reactive power consumed by the system if 2.5 A rms current is drawn ?
63.Which of the followings can produce maximum induced voltage ?
64. In a series RLC circuit, if the frequency is less than the resonant frequency, then
65. The conductivity of a metal is determined by
66. A superconductor may be used for generating
67. Increase in percentage of carbon in carbon steel reduces
68.The magnetic field required to reduce the residual magnetisation to zero is called
69. A transformer transforms
70. In a power transformer, the core loss is 50 W at 40 Hz and 100 W at 60 Hz,under the condition of same flux density in both cases. The core loss at 50 Hz will be
71. In a transformer, the primary ampere turns are counter balanced by
72. The voltage regulation of a transformer having 02 % resistance and 05 % reactance, at full load, 0.8 power factor lagging is
73. A single phase transformer has a maximum efficiency of 90 % at full load and unity power factor. Efficiency at half load at same power factor will be
74. Grain oriented laminated sheet steel in a transformer reduces
75. The windings used in a 03 phase shell type transformer is __________ type.
76. Two transformers when operating in parallel will share the load depending upon which of the followings ?
77. Stray losses in an electrical machine are sum of
78. The teeth in an armature of a DC machine are sometimes skewed. This is done to reduce
79. An 8 pole DC generator has a single wave wound armature containing 32 coils of 6 turns each. The flux per pole is 0.06 Wb. If the generator is running at 250 RPM, the induced armature voltage will be
80. In a DC machine, the no. of mechanical and electrical degrees will be same when the no. of poles in the machine are
81. The output indicated on the name plate of any motor is always the
82. The efficiency of a DC motor when developing maximum power will be about
83. At 1200 RPM, the induced emf of a DC machine is 200 V. For an armature current of 15 A, the electromagnetic torque produced will be
84. The efficiency of a DC series machine cannot be determined by Swinburne’s test as
85. Three phase alternators are invariably connected in Star so as to
86. The armature reaction effect in a synchronous machine depends on
87. Synchronous motors generally have
88. A 10 pole, 25 Hz alternator is directly coupled to and is driven by 60 Hz Synchronous motor. What is the no. of poles for the synchronous motor ?
89. Variation in DC excitation of a synchronous motor causes variations in
90. The phenomenon of oscillation of the rotor of a synchronous motor about its equilibrium position corresponding to new load on sudden throwing off or increase of load is called
91. A Reluctance motor
92. The rotor of a Stepper motor has
93. In an induction motor, if the air gap is increased, then
94. The slip of a 400 V, 3 phase, 4 pole, 50 Hz machine running at 1440 rpm is
95. The frequency of rotor current at standstill is equal to
96. In a double cage induction motor, the inner cage has
97. The speed of a 3 phase slip ring induction motor can be controlled from the rotor side by
98. Capacitor start and capacitor run motors are used in
99. The function of steel wire in an ACSR conductor is to
100. The string efficiency of a string of suspension insulators is dependent on
101. Which one of the followings does not have an effect on corona ?
102. When a fault occurs in a high voltage transmission line, first
103. Which motor should not be used in centrifugal pump ?
104. For quick reversal, the motor preferred is
105. In an electric press, mica is used
106. The power factor at which the direct arc furnace operates is
107. An advantage of PMMC instruments is that it
108. Dynamometer type wattmeter are suitable for
109. Which of the following effects can be caused by a rise in the temperature ?
110. An increase in the base recombination of a BJT will increase
111. Negative feedback in an amplifier
112. An ideal Op-amp has which of the following characteristics ?
113. For the circuit shown below, the output (F) is given by
