Paper Code:- 35/2016 Date Of Test:-25.02.2016
Maximum : 100 marks
Time: 1 hour and 15 minutes
1.Arc heating occurs when the air between electrodes of opposite polarity becomes :
(A) Moistened
(B) Dry
(C) Ionized
(D) None of the above
2.The meter used to measure the temperature of a furnace is :
(A) hydrometer
(B) pyrometer
(C) hygrometer
(D) tachometer
3.Which part is provided in a battery charger to prevent the flow of excessive current into the
battery?
(A) Coarse selector
(B) Time selector switch
(C) Limiting resistance
(D) Transformer
4.What will happen to the filter circuit in battery charger if the output filter capacitor is
opened?
(A) Will not function
(B) Will make humming noise
(C) More current will flow
(D) No output voltage
5.What are the two relative quantities to be plotted for external characteristics curve for
DC shunt generator?
(A) Field current Vs No load voltage (B) Armature current Vs Induced e.m.f
(C) Load current Vs Terminal voltage (D) Load current Vs Induced e.m.f
6.What will happen to a self excited DC generator, if the generator runs in reverse direction?
(A) The induced e.m.f. is increased
(B) There is no change in the induced e.m.f.
(C) Spark will be produced in the commutator
(D) Residual magnetism in the pole will be destroyed
7.Which is the application of delayed response type diazed fuse?
(A) Motor circuits
(B) Heating circuits
(C) Lighting circuits
(D) Electronic circuits
8.The force between two long parallel conductors is inversely proportional to :
(A) current in one conductor
(B) distance between the conductors
(C) radius of conductors
(D) product of current in two conductors
9.Which of the following circuit elements will oppose the change in the circuit current?
(A) Inductance
(B) Resistance
(C) Capacitance
(D) All of the above
10. The colour of light of mercury vapour lamp is :
(A) Greenish blue
(C) Pink
(B) Yellow
(D) White
11. Which of the following frequencies has the longest time period?
(A) 1 Hz
(B) 1 kHz
(C) 10 Hz
(D) 10 kHz
12. In a generator maximum value of e.m.f. is generated within the coil axis is at:
(A) 45° with field axis
(B) 90° with field axis
(C) 180° with field axis
(D) Zero degree with field axis
13.
A choke coil of operating fluorescent lamp is short-circuited. What is the consequence?
(A) The lamp becomes brighter
(B) The lamp becomes less bright
(C) The current becomes so large that it damages the tube
(D) The short circuit is noticed only after the lamp is switched 'ON' again
14. A contactor coil is designed for 220V DC. What happens if it is connected to 220 V AC?
(A) Too large a current is drawn by the coil and it is destroyed
(B) Too small a current is drawn by the coil and the operation of the contactor is no
longer certain
(C) It draws the same current
(D) It works better
15. A capacitor is connected across a 200 V AC line. Its minimum voltage rating should be:
(A) 100 volt
(B) 200 volt
(C) 300 volt
(D) 400 volt
16. The power factor of 3-phase load is less than 0.5. While measuring power by two
watt meters:
(A) one of the wattmeters gives zero reading
(B) one of the wattmeters gives negative reading
(C) both wattmeters give positive reading
(D) one of the wattmeters kicks backward
17. Voltage required to operate the Neon sign tubes depends upon :
(A) Diameter of the tube
(B) Gases in the tube
(C) Length of the tube
(D) Thickness of the tube
18. Soldering of a Britannia joint is a necessity to avoid loosening of the joint due to :
(A) Vibrations and change in atmospheric temperature
(B) Corrosion due to galvanic action
(C) Corrosion due to atmospheric changes
(D) Overheating
19. The testing of wiring installation for insulation resistance to ensure that:
(A) All conductors have high ohmic values in the circuit
(B) All outlet points are earthed properly to ground
(C) Leakage current beyond the stipulated value does not flow to earth
(D) Live and neutral conductors in the installation are continuous
20. Braking torque in energy meter is produced to:
(A) Brake the instrument
(B) Bring energy meter to stand still
(C) Safeguard it against creep
(D) Maintain steady speed and equal to driving torque
21. The scale of dynamometer type wattmeter is of:
(A) Uniform scale
(B) Logarithmic scale
(C) Non-linear scale
(D) Square law scale
22. The standard secondary voltage for a PT used in power system in :
(A) 1V
(B) 5 V
(C) 50 V
(D) 110 V
23.Which instrument always indicates true r.m.s. value irrespective of the waveform?
(A) Moving iron meter
(B) Digital voltmeter
(C) Thermocouple meter
(D) None of the above
24. A voltmeter gives inaccurate reading to measure the drop across a low resistance because :
(A) The higher scale has been selected
(B) The current drawn by the meter is too low
(C) The sensitivity of the meter is too low
(D) None of the above
25.The phase difference between the currents in the two pressure coils in PF meter is :
(A) Approximately 0°
(B) Approximately 90°
(C) Exactly 0
(D) Exactly 90°
26. When a rewound armature is rolled on the surface of a leveled surface plate the armature
stops at the same position of its periphery for each rolling, the portion of armature touching
the surface plate is regarded to have :
(A) higher weight than the diametrically opposite portion
(B) lesser weight than the diametrically opposite portion
(C) equal weight to that of opposite portion
(D) higher weight than the portion 90° to it on any one side
27.
Which one of the following characteristic is NOT applicable to synchronous motors?
(A) Runs at constant speed at all loads
(B) Suitable to supply only mechanical load
(C) Can also be used for PF improvement
(D) Not self starting
28. Which method is generally adopted to measure the power in a three phase imbalanced load
system?
(A) One wattmeter method
(B) Two wattmeter method
(C) Three voltmeter method
(D) Three wattmeter method
29. The colour of light depends upon :
(A) Wave length
(C) Speed of light
(B) Frequency
(D) Frequency and wave length
30. Which of the following lamp is a cold cathode lamp?
(A) Neon lamp
(B) Sodium vapour lamp
(C) Mercury vapour lamp
(D) Fluorescent lamp
31. You have to repair storage type water heater which has steam in the hot water. The possible
remedy for this trouble can be found by checking:
(A) All points for possible leakages (B) The thermostat setting
(C) All wiring for loose connections (D) Element for its condition
32. The reading on a 3 digit millivoltmeter started flashing continuously when connected acro
a resistor to measure the mV across it. The reason for flashing of display on millivoltmeter is
that:
(A) The battery in the instrument is weak (B) There is no battery in the instrument
(C) The measured value is over range (D) The display is damaged
33.Which one of the following measurement CANNOT be done with multimeter?
.(A)Current drawn by an electronic circuit
(B)Supply voltage to DC motor
(C)Continuity test of motor winding
(I))Insulation resistance of motor
34.Why a higher capacity squirrel cage induction motor is not recommended for operating under
low load condition?
(A)Voltage drop in line will be too much
(B)Power factor will be less
(C)Higher capacity motors does not run at constant speed
(D)Torque is too much hence it may cause damage
35.Shunts and multipliers used in MC instruments are made up of Mangnin. The reason for
using the above metal is that, it has:
(A)Positive temperature co -efficient of resistance
(B)Negative temperature co -efficient of resistance
(C)
Perfectly constant temperature co -efficient of resistance
(D)Very low (practically constant) temperature co -efficient of resistance
36.In order to operate a fluorescent tube set on DC suPply, which of the following additional
auxiliary device is to be connected?
(A)Inductance
(B)Capacitance
(C)Resistance
(D)No extra device is needed
37.The power input increases by three times when the connection of three phase loads changes
from star to delta at the same line voltage. What is the reason for this?
(A)The voltage across one phase of the load is three times higher in delta connection
than in star connection
(B)The power factor increases by three times in delta connection when compared to
star connection
(C)The line current is three times higher in delta connection than in star connection
(D) . The voltage in each phase increases by two times and the currant by 1.732 times
38.In a parallel resonant circuit the capacitor current is:
(A)More than line current
(B)Less than line current
(C)Equal to line current
(D)None of the above
39.According to National electric code what is the specified minimum distance between the
washing unit and the switch board:
(A)0.6 metre
(B)1.3 metre
(C)2.5 metre
(D)3.4 metre
40A series Ride circuit takes leading power factor current at:
(A)Resonant frequency
(B)More than resonant frequency
(C)Less than resonant frequency
(D)None of the above
41.In the output voltage of a DC generator the ripple effects can be reduced by increasing the:
(A)Field current
(B)Number of armature coil
,
(C)Number of turns in the field winding
(D)Size of the conductor of the armature coil
42.While installing power sub -circuits in domestic installations it should be restricted to:
(A)800 watts with in 10 light and fan points
(B)800 watts within 2 outlets
(C)3000 watts within 10 light and fan points
(D)3000 watts within 2 outlets
43.What type of compounding would be desirable in the DC generator feeding a long
transmission line?
(A) Over compounding
(B)Under compounding
(C)Flat compounding
(D)Any one of the above
44.The most economic method of electrical braking ía:
(A)Plugging
(B)Dynamic braking with self excitation
(C)Regenerative braking
(D)Dynamic braking with separate excitation
45.When a DC series motor is connected to an AC supply. then:
(A)It will stop
(B)it may burnt out
(C)It will run without any trouble
(D)It will run with less efficiency and high spark at commutator
46.Dummy coils in a DC generator is provided:
(A)To amplify voltage
(B)To reduce eddy current losses
(C)To enhance flux density
(D)To provide mechanical balance to the rotor
47.When the number of poles and the number of armature conductors are fixed, then which
winding of a DC generator will give the higher e.m.f.?
(A)Wave winding
(B)Lap winding
(C)Same e.m.f. in tap and wave winding
(D)Depends on other features of design
48.Earth tester is used for measuring earth resistance in which generated DC is converted into
AC by current reverser. The reason for using AC supply for resistance measurement is:
(A)AC resistance is more than DC resistance
(B)To reduce error due to electrolytic e.m.f.
(C)AC wave form is pulsating in nature
(D)AC contains sine wave form
49.The basic function of voltage stabilizer is to provide:
(A)Constant current supply to load
(B)Constant power supply to load
(C)Constant voltage supply to load
(D)Uninterrupted supply to load
50.A food mixture rated for 240 V AC fails to start when it is switched on. Which one of the
following is NOT a cause for the above?
(A)Jammed rotor
(B)Supply voltage is only 210 V
(C)OL relay is not re -set
(I))Open in armature winding
51.In a transformer the leakage flux may be minimized by:
(A)Minimizing the number of turns of both the winding
(B)Sectionalizing and interleaving the primary and secondary winding
(C)Keeping the magnetizing current to the minimum
(D))Reducing the reluctance of the iron core to the minimum.
52.Which one of the following connections is preferred for three -to -two phase conversion?
(A)Scott
(B)Double scott
(C)Star/star
(D)Star/double — delta
53.The phase relationship between primary and secondary terminal voltage of a transformer is:
(A)Primary voltage is leading the secondary voltage by 90°
(13)Secondary voltage is leading the primary voltage by 90°
(C)180° out of phase
(D)In the same phase
54The no load primary current in an ideal transformer is:
(A)In phase with VI
(B)Leads VI by 90°
(C) Lags behind V1 by 90°
(I))Lags Vt by an angle lying between Ce and 90°
55.An Optocoupler is a single package of:
(A)LED and a signal diode
(13)LED and n photodiode
(C)Two photodiodes
(D)Two LEDs
56. One of the diode of a bridge rectifier connected to 100 V 50 Hz AC input is found to be
damaged. The DC output of the circuit is 90 V. The minimum value of PIV of the diode
required for replacement is:
(A) 45V (B) 50 V
(C) 100 V (D) 150V
57. You are working with a fully automatic star delta starter. You notice that when start switch
is pressed the motor starts in star but does not change to delta. The trouble will be in:
(A) Delta contactor (B) Timer and its circuit
(C) Star contactor (D) Line contactor
58. Watt-hour meter is classified as a:
(A) Deflecting instrument (B) Indicating instrument
(C) Recording instrument (D) Integrating instrument
59. Two pin sockets should not be used in domestic wiring unless the appliance to be connected
is:
(A) Double earthed (B) Double insulated
(C) Controlled by ELCII (D) Controlled by MCB
60. As load on induction motor increases its power factor:
(A) Remain constant
(B) Goes on decreasing
(C) Goes on increasing over after full load
(D) Goes on increasing up to full load and then it falls again
61. During no load test of a 3 phase induction motor, the motor draws power:
(A) For core loss and copper loss
(B) For copper loss and windage -friction loss
(C) For core loss and windage -friction loss
(D) Only for very small copper loss
62. The recent method of smooth speed control of a three-phase induction motor over a wide
range is:
(A) Frequency control method (B) Rotor resistance control method
(C) Voltage control method (I)) None of the above methods
63. Rotor bars of squirrel cage rotor are sometimes skewed :
(A) To prevent rotor from aligning and locking up with stator
(B) To give more uniform torque
(C) To reduce humming noise
(D) Due to all above reasons
64. For 66 kV lines the number of insulator discs used is:
(A) 3 (B) 6
(C) 10 (D) 12
65. AC resistance of a line conductor is more than its DC resistance because of:
(A) Skin effect (B) Proximity effect
(C) Skin effect and proximity effect (I)) None of these
66. What type of insulator will be used if the direction of the transmission line is changed?
(A) Strain type (B) Shackle type
(C) Pin type (D) Suspension type
67. The back emf set up in the armature of a synchronous motor depends on;
(A) Rotor speed only
(13) Rotor excitation only
(C) Rotor excitation and rotor speed
(D) Coupling angle, rotor speed and excitation
68. The current drawn by an over excited synchronous motor will be;
(A) Depending on the nature of load (B) At lagging power factor
(C) At leading power factor (D) At unity power factor
69. Two alternators are sharing an inductive toad equally. What will be happened if the
excitation of one alternator is increased?
(A) Another alternator will deliver more current
(B) Another alternator will deliver less current
(C) Both will continue to share load equally
(D) Both will deliver more current
70. A ceiling fan rotates slowly in either direction. The probable fault is:
(A) . An open in centrifugal switch (13) An open in capacitor
(C) Short in the capacitor (D) Blown fuse
71. In repulsion motor, maximum torque is developed when:
(A) Brush axis is at 180 0 electrical to the field axis
(S) Brush axis is at 90° electrical to the field aids
(C) Brush axis is at 45° electrical to the field axis
(D) Brush axis coincides with the field axis
72. Starting winding of a single phase motor of a refrigerator is disconnected from the circuit by
means of a:
(A) Centrifugal switch
(B) Magnetic relay
(C) Thermal relay
(I)) None of the above
73. How the speed control of universal motor used for sewing machine is done?
(A) Introducing friction mechanism
(B) Tapping the field at various point
(C) Centrifugal mechanism
(D) Introducing a variable resistance in series with the motor
74. Buchholz relay is operated by:
(A) Gas pressure (B) Eddy current
(C) Electrostatic induction (D) Electromagnetic induction
75. The size of earth wire is determined by;
(A) the atmospheric condition
(B) the voltage of the service wires
(C) the current capacity of the service wires
(D) none of these
76. Earthing in consumer premises is necessary to give protection against:
(A) Overloading (B) Danger of electric shock
(C) Voltage fluctuation (D) High temperature of the conductors
77. A single phase protection switch is used to protect:
(A) The distribution transformer
(B) The motor in case of fuse failure
(C) The motor from the daniage due to single phasing
(D) From the maximum starting current of motor
78. The best location of the power factor improving device to be installed in the transmission line
is at:
(A) The receiving end (B) The sending end
(C) Middle of the line (D) Any place
79. motor has series characteristics.
(A) Capacitor start motor (B) Shaded pole motor
(C) Repulsion motor (D) None of the above
80. How the light output is produced in electric discharge lamp?
(A) By heating effect of current (B) By magnetic effect of current
(C) By ionisation in a gas or vapour (D) By cathode ray emission
81. A social Reformer of Kerala who started Atmavidhya Sangham was:
(A) Vaikunda Swamikal (B) Brahmananda Sivayogi
(C) Thycaud AyyaVaikunda (D) Vagbhadanandan
035/2016 12 A
82. "The Career and legend of VascodaGama" is a book written by:
(A) Sanjay Subramaniyam (B) Arun Shourie
(C) Kushwant Singh (D) None of these
83. Who among the foreign travellers made earliest reference regarding Kerala?
(A) Marco Polo (B) Megasthanese
(C) Ptolemy (D) Pliny
84. The Newspaper "Sujananandini" was started by:
(A) C.V. Kunhiraman (B) C. Krishnan
(C) Kesavan Asan (D) Sahodaran Ayyapan
85. Under 42nd
amendment to our constitution the fundamental duties were enumerated This
• concept of fundamental duties was borrowed from the constitution of:
(A) USSR (B) Ireland •
(C) China (D) UK
86. The Rajya Sabha is a body.
(A) a part of the Lok Sabha (B) a temporary body
(C) a permanent body (D) none of these
87. Article 368 deals with:
(A) Special Provision for Jammu and Kashmir
(13) President rule in a state
(C) Pertains to the abolition of untouchability
(D) Amendment of the Constitution
88. "Neel Darpan" is a play which portrays the oppression meted out by the indigo planters over
the peasants. This famous Play was written by whom?
(A) Raja Ram Mohan Roy (B) Dinbandhu Mitra
(C) Jyothirao Phttle (D) R.N. Tager°
89. Which of the following is one of the Harappan sites related to the maritime activities of the
Harappan people?
(A) Lothal (B) Kalibangan
(C) Rangpur (D) Mohanjodaro
90. The cold current which meets with the warm gulf stream near Newfoundland?
(A) Humboldt (B) Canaries
(C) Benguala (D) Labrador
91. South Africa was captured by Britain after the war.
(A) Opium war (B) Boer war
(C) Boxer Rebellion (D) Carnatic war
92. The King of England during the American war of independence:
(A) George MI (B) George ln
(C) Henry VIII (I)) Charles Ia
93. The classical dance form popular in the North-East parts of India:
(A) Bihu (B) Chiraw
(C) Nlanipuri (D) Kathak
94. The author of the famous book "Fidelio" :
(A) T.S. Eliot (B) L. Beethoven
(C) Lord Byron (D) George Bernard Shaw
95. The Headquarters of Economic and Social Commission for Asia and the Pacific (ESCAP) is at:
(A) Jakarta (R) Manila
(C) Kathmandu (D) Bangkok
96. Language in which maximum number of Newspapersare published?
(A) Marathi (B) English
(C) Hindi (D) Bengali
97. French official book:
(A) Yellow book (B) White book
(C) Green book (D) Blue book
98. The author of "Truth, Love and a Little Malice":
(A) Boris Pasternak (B) U. Thant
(C) Amita Malik (D) Khushwant Singh
99. Who was the founder of Scientific Astronomy?
(A) Hippalus (B) Hoffmann
(C) Hippocrates (D) None of these
100. Who propounded the signs of the Zodiac?
(A) Indians (B) Egyptians
(C) Babylonians (D) None of these
035/2016 14 A