ELECTRICAL ENGINEERING TERMS
SET-A
1. In the transformers
A.
B.
C.
D.
high tension winding is used near the core
high tension winding is used away from the core
low tension winding is used near the core
low tension winding is used away from the core
2. Which of the following parameters can be neglected for a short line?
A. resistance
C. reactance
B. inductance
D. capacitance
3. The curve representing Ohm’s law is
A. a parabola
C. a sine function
B. linear
D. a hyperbola
4. The overcurrent protective device is caused to operate by ________
A. voltage surge
C. voltage drop
B. current flow
D. impedance
5. What is the maximum number of bends permitted in rigid conduits between outlets?
A. 4 quarter bends
C. 2 quarter bends
B. 6 quarter bends
D. 3 quarter bends
6. Which of the following insulators will be selected for high voltage application?
A. strain type
C. suspension type
B. disc type
D. pin type
7. If the torque angle δ continuously increases, system will become
A. stable
C. oscillatory stable
B. unstable
D. asymptotic stable
8.
A.
B.
C.
D.
The condition in Ohm’s law is that
ratio V/I should be constant
current should be proportional to voltage
the temperature should remain constant
the temperature should vary
9. Which of the following shall be included in the calculation of the reliability
standard indices of the distributor asset by the Philippine Distribution Code?
A. Outages that occur on the secondary lines of the distribution system
B. Planned outages where the customers have been notified at least three (3) days prior
to the loss of power
C. Outages that occur on the primary lines of the distribution system
D. Outages that occur in the transmission line
10. A type of electronics communication in which only one party transmits at a time.
A. Full duplex
C. Bicom
B. Half duplex
D. Simplex
11. Base load plants are designed to supply power at
A. low capital cost and low operating cost
B. high capital cost and low operating cost
C. low capital cost and high operating cost
D. high capital cost and high operating cost
12. Peak load plants are designed to supply power at
A. low capital cost and low operating cost
B. high capital cost and low operating cost
C. low capital cost and high operating cost
D. high capital cost and high operating cost
13. If the effect of earth is taken into account, then the capacitance of line to ground
A. decrease
C. remain unchanged
B. increase
D. become infinite
14. The effective resistance of conductor is increased by
A. skin effect
C. corona effect
B. proximity effect
D. both (a) and (b)
15. A two terminal pair of network of a transmission line can be represented by a
A. π-network
C. either (a) or (b)
B. T-network
D. three network
16. In television system, channels 2 and 13 are classified as
A. VHF
C. SHF
B. UHF
D. EHF
17. An ACSR conductor has (n-1) layers around its single center strand, the total number
of strands will be
A. 3n2 + 3n + 1
C. 3n2 + 3n - 1
B. 3n2 - 3n - 1
D. 3n2 - 3n + 1
18. Which of the following methods of generating electric power from the sea water is
more advantageous?
A. water power
C. Tidal power
B. ocean power
D. none of these
19. When installing two grounding electrodes, the minimum distance between them is
A. 1,800 mm
C. 1,500 mm
B. 2,000 mm
D. 2,400 mm
20. The current flowing in L and C at parallel resonance are
A. zero
C. infinite
B. equal
D. different
21. What does PEMC in EPIRA stands for?
A. Philippine Energy Market Corporation
B. Private Energy Marketing Company
C. Philippine Electricity Market Corporation
D. Philippine Electrical Marketing Corporation
22. For two alternators operating in parallel, if the load shared by one of them is to be
increased, its field excitation is
A. to be strengthened keeping input torque the same
B. to be weakened keeping input torque the same
C. to be kept constant but input torque should be increased
D. to be kept constant but input torque should be decreased
23. Open circuit test on transformers is conducted to determine
A. hysteresis loss
C. core loss
B. copper loss
D. eddy current loss
24. Which of the following power plant is a conventional source of energy
A. Solar energy
C. Coal energy
B. Geothermal energy
D. Wind energy
25. In a synchronous motor, the magnitude of stator back emf depends on
A. load on the motor
C. both the speed and rotor flux
B. dc excitation only
D. none of these
26. Alternators installed in a hydro power plant, are of
A. low speed
C. medium speed
B. high speed
D. very high speed
27. In a loss-free RLC circuit, the transient current is
A. oscillating
C. sinusoidal
B. square wave
D. non-oscillating
28. At very low frequencies a series RC circuit behaves as almost purely
A. resistive
C. capacitive
B. inductive
D. none of these
29. One of the advantages of distributing the winding in alternators is to
A. reduce harmonics
C. improve voltage waveform
B. reduce the amount of copper
D. decrease the value of the voltage
30. The effect of corona is
A. increased reactance
B. increased inductance
C. increased energy loss
D. all of these
31. The rms value of pure cosine function is
A. 0.5 of peak value
C. same as peak value
B. 0.707 of peak value
D. zero
32. What is the equivalent IEEE device function number for directional power relay
A. 21
C. 37
B. 32
D. 87
33. Energy radiated continuously in the form of lighting waves is called?
A. luminous intensity
C. luminous flux
B. lumen
D. illumination
34. Efficiency is secondary consideration in case of
A. base load plants
C. both base load and peak load plants
B. peak load plants
D. none of these
35. The condition of a liquid electrolyte is measured in terms of its
A. current value
C. acid content
B. specific gravity
D. voltage output
36. If the field of a dc shunt motor is opened
A. it will continue to run at its rated speed
B. the speed of the motor will become very high
C. the motor will stop
D. the speed of the motor will decrease
37. An ideal full-wave rectifier with non-inductive load has zero transformation losses.
What is the efficiency?
A. 70%
B. 80%
C. 90%
D. 100%
38. The dummy coil in dc machines is used to
A. eliminate reactance voltage
B. eliminate armature reactance
C. bring about mechanical balance of armature
D. eliminate harmonics developed in the machine
39. The purpose of insulating oil when used on power circuit breaker are the following,
EXCEPT;
A. Coolant
C. Quencher
B. Interrupter
D. Insulation
40. Inside a hollow spherical conductor
A. electric field is zero
B. electric field is constant
C. electric field changes with distance from the center of the sphere
D. electric field is unity
41. Residual magnetism is necessary in a
A. separately excited generator
C. both of these
B. self-excited generator
D. none of these
42. In case of delta connected circuit, when one resistor is open, power will be
A. unaltered
C. reduced to 1/16
B. reduced to 1/9
D. reduced by 1/3
43. Transient current in an RLC circuit is oscillatory when
A. R =0
C. R > √
B. R = √
D. R < √
44. With reference to armature windings, wave windings are often called _________
windings.
A. concentric
C. parallel
B. series
D. ring
45. This is the compact arrangement of switching devices;
A. Circuit protector
C. Switchgear
B. Switchboard
D. Panelboard
46. Which of the following is NOT INCLUDED in the Technical Performance Standards for
Distribution and Supply set by the Philippine Distribution Code?
A. Power Quality
C. Collection Efficiency
B. Reliability
D. System Efficiency
47. Which plant takes the least time in starting from cold condition to full load
operation?
A. Steam turbine power plant
C. Gas turbine power plant
B. Hydro power plant
D. Nuclear power plant
48. What is the equivalent IEEE device number for an under-voltage relay?
A. 67
C. 27
B. 52
D. 51
49. To adjust the power of the alternator, adjust the _______________.
A. power factor
C. field current
B. governor
D. frequency
50. In a transmission line of negligible resistance, the surge impedance will be
_______________.
A. square root of LC
C. square root of 1/LC
B. square root of L/C
D. square root of C/L
51. What is the purpose of reactor in short circuit?
A. To open the line in short circuit
B. To decrease the circuit resistance
C. To lessen the current in short circuit
D. To increase the current in short circuit
52. What is the maximum output power of a cellular transmitter?
A. 4.5 w
C. 3 w
B. 1.5 w
D. 6 w
53. For constant transmission efficiency, voltage is increased n times, the size of the
conductor would be _____________
A.
B.
C.
D.
reduced to (1/n) times of the original
reduced to (1/n2) times of the original
increased to n2 times of the original
increased ton times of the original
54. Copper loss of a transformer is determined by means of a/an ____ test.
A. open-circuit
C. short-circuit
B. polarity
D. inductive-circuit
55. The power transmission capacity of the transmission is ____________ .
A. inversely proportional to the voltage
B. directly proportional to the voltage
C. proportional to the square of the voltage
D. proportional to the cable of the voltage
56. The under voltage relays are usually used for what protection of the electrical
equipment?
A. feeder protection
C. transformer protection
B. motor protection
D. bus-bar protection
57. Which of the following type of fault used only the equivalent positive sequence
impedance of the circuit in the short circuit calculation?
A. Line to Line
C. Double line to ground
B. Line to ground
D. Three-phase fault
58. What device used to measure the temperature of a motor winding while the motor is in
operation?
A. Seismic probe
C. Thermocouples
B. Resistance temperature detector
D. Proximity probe
59. Which of the following is a primary disadvantage of FM over AM?
A. Lower efficiency
C. Higher cost and complexity
B. Noise susceptibility
D. Excessive use of spectrum space
60. Which of the following that the voltage regulation is one of the important factors
consider in the electrical power design?
A. generator
C. feeder
B. transmission line
D. transformer
61. Which of these is not a factor in the selection of fuse rating for protection of a
branch circuit?
A. Branch full-load current
C. Branch fault-current
B. System impedance
D. System voltage
62. Which of the following principle will the operation of fiber-optic cable is based?
A. dispersion
C. reflection
B. refraction
D. absorption
63. When the voltage remains the same, the current will ___________ as the impedance
decrease
I. decrease
II. Increase
A. I only
B. Both
C. Either I or II
D. II only
64. When electrons build up pressure at one point, it is called ________.
A. ganging
C. impedance
B. current flow
D. pressure filing
65. Which of the following type of fault used only the equivalent positive and negative
sequence impedance of the circuit in the short-circuit calculation?
A. Double line to ground
C. Three-phase
B. Line to line
D. Line to ground
66. Based on the Philippine Distribution Code, all users of the distribution system must
maintain a certain power factor at the connection point in order to maintain power
quality in the system. What power factor should be maintained at the connection point?
A. Not less than 65%
C. Not less than 85%
B. Not less than 70%
D. Not less than 75%
67. Which of the following is not considered in the selection of surge arrester?
A. Voltage rating
C. Class of Arrester
B. Current rating
D. Insulation level
68. In full-wave rectification, if the input frequency is 60 Hz, then output has a
frequency of ___________.
A. 30 HZ
C. 120 HZ
B. 60 HZ
D. 240 HZ
69. The specific gravity of a lead-acid cell is often used as a measure of its
______________.
A. rate of discharge
C. state of charge
B. operating temperature
D. life expectancy
70. The commonly used light sensor in a modern fax machine is the_________.
A. photo tube
C. charge couple device
B. photo transistor
D. liquid crystal display
71. A standard candle emits a total luminous flux of _____________ lumens.
A. 12.57
C. 78.96
B. 25.14
D. 157.90
72. A space station with communication equipment that synchronizes with earth’s orbit.
A. space craft
C. satellite
B. space probe
D. scape CATV
73. Impurities in an electrolyte can cause an internal short circuit condition called
A. local action
C. polarization
B. depolarization
D. electrolysis
74. As load power factor of an alternator becomes more lagging, the value of generated
voltage required to give rated terminal voltage ____________.
A. increase
C. remains unchanged
B. decrease
D. varies with rotor speed
75. In a commutator
A. copper is harder than mica
B. mica and copper are equally hard
C. mica is harder than copper
D. none of these
76. The changes in volume of transformer cooling oil due to variation of atmospheric
temperature during day and night is taken care of by which part of transformer?
A. Conservator
C. Bushings
B. Breather
D. Buchholz relay
77. Centrifugal switch disconnects the auxiliary winding of the motor at about _________
percent of synchronous speed.
A. 30 to 40
C. 80 to 90
B. 70 to 80
D. 100
78. The material commonly used for insulation in high voltage cables is
A. lead
C. rubber
B. paper
D. glass
79. For a series RLC circuit at resonance, the current amplitude is _______ for a fixed
voltage amplitude and the power factor is _________.
A. minimum, zero
C. maximum, zero
B. minimum, unity
D. maximum, unity
80. If the length of a cable is doubled, its capacitance
A. becomes one-fourth
C. becomes double
B. becomes one-half
D. remains unchanged
81. Wye-delta starting is equivalent to autotransformer starting with ___________
tapping.
A. 73%
B. 67%
C. 58%
D. 33%
82. These days DC motors are widely used in
A. pumping sets
C. electric tractions
B. air compressors
D. machine shops
83. Breather mounted on transformer tank contains
A. water
C. liquid
B. oil
D. calcium
84. As load power factor of an alternator becomes more leading, the value of generated
voltage required to give rated terminal voltage ____________.
A. increase
C. remains unchanged
B. decrease
D. varies with rotor speed
85. The process by which metallic parts are demagnetized is called ______.
A. degaussing
C. degrading
B. demagnetizing
D. degreasing
86. Synchronous motors are
A. self-starting
B. not self-starting
C. essentially self-starting
D. none of these
87. It is difficult to magnetize steel because of its
A. high density
C. low permeability
B. high retentivity
D. high permeability
88. Present day capacitors which have high capacitance in small size use a diameter of
A. paper
C. ceramic
B. rubber
D. Mylar
89. The current-carrying capacity of a copper wire having twice diameter of another
copper wire is __________.
A. twice
C. three times
B. four times
D. half
90. What kind of device is a diode?
A. Bilateral
B. Linear
C. Unipolar
D. Nonlinear
91. If the line frequency is 60 Hz, the output frequency of a bridge rectifier is
A. 30 Hz
C. 120 Hz
B. 60 Hz
D. 240 Hz
92. In a shunt generator the voltage builds up till constrained by
A. speed limitation
C. saturation of iron
B. armature heating
D. insulation restriction
93. Slip rings are made of
A. steel
C. Bakelite
B. copper
D. mica
94. For proper parallel operation, ac polyphase alternators must have the same
______________.
A. speed
C. Voltage rating
B. KVA rating
D. excitation
95. The series field of a short-shunt compound dc generator is excited by ___________
current.
A. shunt
C. load
B. armature
D. external
96. The reciprocal of permeability is
A. conductivity
C. reluctivity
B. susceptibility
D. permittivity
97. For which of the following sinusoids, the rms value and mean value is the same?
A. sine wave
C. square wave
B. triangular wave
D. half wave rectified
98. The maximum efficiency of a half-wave rectifier is ___________.
A. 40.6%
C. 50%
B. 80.6%
D. 20.3%
99. Ideal transformer assumptions do not include
A. no leakage flux
C. zero resistance of the winding
B. no saturation of core
D. zero reactance of the winding
100. If the load current and flux of a dc motor are held constant and voltage applied
across its armature is increased by 10 percent, its speed will _____________.
A. decrease by about 10%
C. increase by about 10%
B. remain uncharged
D. depend on armature resistance
ANSWERS
1.1.A A
2.2.D D
3.3.B B
4.4.B B
5.5.A A
6.6.C C
7.7.B B
8.8.C C
9.9.C C
10.
10.B B
11.
11.B B
12.
12.C C
13.
13.B B
14.
14.D D
15.
15.C C
16.
16.A A
17.
17.D D
18.
18.C C
19.
19.A A
20.
20.B B
21.
21.C C
22.
22.C C
23.
23.C C
24.
24.C C
25.
25.B B
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
C
C
C
C
C
B
B
C
B
B
B
B
C
B
A
B
D
D
B
C
C
C
C
B
B
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
62.
63.
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
75.
C
C
B
C
C
B
D
B
D
C
B
C
D
B
B
C
D
C
C
C
A
C
A
A
C
76. A
77. B
78. B
79. D
80. C
81. C
82. C
83. D
84. B
85. A
86. B
87. C
88. C
89. B
90. D
91. C
92. C
93. B
94. C
95. C
96. C
97. C
98. A
99. D
100. C