Previous Exams

Electrician(Water Transport) - 2016

 

Time Remaining :
1. Which of the following frequencies has the longest time period?
1Hz

1 kHz

10 Hz

10 kHz
2. In a generator maximum value of e.m.f.is generated within the coil axis is at:
45 degree with field axis

90 degree with field axis

180 degree with field axis

Zero degree with field axis
3. A choke coil of an operating fluorescent lamp is short-circuited.What is the consequence?
The lamp becomes brighter

The lamp becomes less bright

The current becomes so large that it damages the tube

The short circuit is noticed only after the lamp is switched ‘ON’again
4. A contactor coil is designed for 220V DC.What happens if it is connected to 220 V AC?
Too large a current is drawn by the coil and it is destroyed

Too small a current is drawn by the coil and the operation the contator is no longer certain

It draws the same current

It works better
5. A capacitor is connected across a 200 V AC line.Its minimum voltage rating should be:
100 volt

200 volt

300 volt

400 volt
6. The power factor of 3-phase load is less than 0.5.While measuring power by two watt meters:
One of the wattmeters gives zero reading

One of the wattmeters gives negative reading

Both wattmeters give positive reading

One of the wattmeters kicks backward
7. Voltage required to operate the Neon sign tubes depends upon:
Diameter of the tube

Gases in the tube

Length of the tube

Thickness of the tube
8. Soldering of a Britania Joint is a necessity to avoid loosening of the joint due to:
Vibration and change in atmospheric temperature

Corrosion due to galvanic action

Corrosion due to atmospheric changes

Overheating
9. The testing of wiring installation for insulation resistance to ensure that:
All conductors have high ohmic values in the circuit

All outlet points are earthed properly to ground

Leakage current beyond the stipulated value does not flow to earth

Live and neutral conductors in the installation are continuous
10. Braking torque in energy meter is produced to:
Brake the instrument

Bring energy meter to stand still

Safeguard it against creep

Maintain steady speed and equal to driving torque
11. The scale of dynamometer type wattmeter is of:
Uniform scale

Logarithmic scale

Non-linear scale

Square law scale
12. The standard secondary voltage for PT used in power system in:
1 V

5 V

50V

110 V
13. Which instrument always indicates true r.m.s.value irrespective of the waveform?
Moving iron meter

Digital voltmeter

Thermocouple meter

None of the above
14. A voltmeter gives inaccurate reading to measure the drop across a low resistance because:
The higher scale has been selected

The current drawn by the meter is too low

The sensitivity of the meter is too low

None of the above
15. The phase difference between the currents in the two pressure coils in PF meter is:
Approximately 0 degree

Approximately 90 degree

Exactly 0 degree

Exactly 90 degree
16. 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 plat
Higher weight than the diametrically opposite portion

Lesser weight than the diametrically opposite portion

Equal weight to that of opposite portion

Higher weight than the portion 90 degree to it on any one side
17. Which one of the following characteristic is NOT applicable to synchronous motors?
Runs at constant speed at all loads

Suitable to supply only mechanical load

Can also be used for PF improvement

Not self starting
18. Which method is generally adopted to measure the power in a three phase imbalanced load system?
One wattmeter method

Two wattmeter method

Three voltmeter method

Three wattmeter method
19. The colour of light depends upon:
Wave length

Frequency

Speed of light

Frequency and wave length
20. Which of the following lamp is a cold cathode lamp?
Neon lamp

Sodium vapour lamp

Mercury vapour lamp

Fluorescent lamp
21. 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:
All points for possible leakages

The thermostat setting

All wiring for loose connections

Element for its condition
22. The reading on a 3 digit millivoltmeter started flashing continuously when connected across a resistor to measure the m V across it.The reason for flashing of display on millivoltmeter is that:
The battery in the instrument is weak

There is no battery in the instrument

The measured value is over range

The display is damaged
23. Which one of the following measurement CANNOT be done with multimeter?
Current drawn by an electronic circuit

Supply voltage to DC motor

Continuity test of motor winding

Insulation resistance of motor
24. Why a higher capacity squirrel cage induction motor is not recommended for operating under low load condition?
Voltage drop in line will be too much

Power factor will be less

Higher capacity motors does not run at constant speed

Torque is too much hence it may cause damage
25. Shunts and multipliers used in MC instruments are made up of Mangnin.The reason for using the above metal is that,it has:
Positive temperature Co-efficient of resistance

Negative temperature Co-efficient of resistance

Perfectly constant temperature co-efficient of resistance

Very low(Practically const-ant)temperature co-efficient of resistance
26. In order to operate a fluorescent tubeset on DC supply,which of the following additional auxillary device is to be connected?
Inductance

Capacitance

Resistance

No extra device is needed
27. 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?
The voltage across one phase of the load is three times higher in delta connection than in star connection

The power factor increases by three times in delta connection when compared to star connection

The line current is three times higher in delta connection than in star connection

The voltage in each phase increases by two times and the current by 1.732 times
28. In a parallel resonant circuit the capacitor current is:
More than line current

Less than line current

Equal to line current

None of the above
29. According to National electric code what is the specified minimum distance between the washing unit and the switch board:
0.6 metre

2.5 metre

1.3 metre

3.4 metre
30. A series RLC circuit takes leading power factor current at:
Resonant frequency

More than resonant frequency

Less than resonant frequency

None of the above
31. In the output voltage of a DC generator the ripple effects can be reduced by increasing the:
Field current

Number of armature coil

Number of turns in the field winding

Size of the conductor of the armature coil
32. While installing power sub-circuits in domestic installations it should be restricted to:
800 watts with in 10 light and fan points

800 watts within 2 outlets

3000 watts within 10 light and fan points

3000 watts within 2 outlets
33. What type of compounding would be desirable in the DC generator feeding a long transmission line?
Over compounding

Under compounding

Flat compounding

Any one of the above
34. The most economic method of electrical braking is:
Plugging

Dynamic braking with self excitation

Regenerative braking

Dynamic braking with separate excitation
35. When a DQ series motor is connected to an AC supply,then:
It will stop

It may burnt out

It will run without any trouble

It will run with less efficiency and high spark at commutator
36. Dummy coils in a DC generator is provided:
To ampily voltage

To reduce eddy current losses

To enhance flux density

To provide mechanical balance to the rotor
37. 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?
Wave winding

Lap winding

Same e.m.f.in lap wave winding

Depends on other features of design
38. 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:
AC resistance is more than DC resistance

To reduce error due to electrolytic e.m.f

AC wave form is pulsating in nature

AC contains sine wave form
39. The basic function of voltage stabilizer is to provide:
Constant current supply to load

Constant power supply to load

Constant voltage supply to load

Uniterrupted supply to load
40. A food mixture rated for 240V AC fails to start when it is switched on.Which one of the following is NOT a cause for the above?
Jammed rotor

Supply voltage is only 210V

OL relay is not re-set

Open in armature winding
41. In a transformer the leakage flux may be minimized by:
Minimizing the number of turns of both the winding

Sectionalizing and inter-leaving the primary and secondary winding

Keeping the magnetizing current to the minimum

Reducing the reluctance of the iron core to the minimum
42. Which one of the following connections is preferred for three-to-two phase conversion?
Scott

Double scott

Star/star

Star/Double-delta
43. The phase relationship between primary and secondary terminal voltage of a transformer is:
Primary voltage is leading the secondary voltage by 90 degree

Secondary voltage is leading the primary voltage by 90 degree

180 degree out of phase

In the same phase
44. The no load primary current Io in an ideal transformer is:
In phase with VI

Leads VI by 90 degree

Lags behind VI by 90 degree

Lags VI by an angle lying between 0 degree and 90 degree
45. An optocoupler is a single package of:
LED and a signal diode

LED and a photodiode

Two photodiodes

Two LEDs
46. One of the diode of a bridge rectifier connected to 100 V 50Hz AC input is found to be damaged.The DC output of the circuit is 90V.The minimum value of PIV of the diode required for replacement is:
45 V

50 V

100 V

150 V
47. 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:
Delta contractor

Timer and its circuit

Star contractor

Line contractor
48. Watt-hour meter is classified as a:
Deflecting instrument

Indicating instrument

Recording instrument

Integrating instrument
49. Two pin sockets should not be used in domestic wiring unless the appliance to be connected is:
Double earth

Double insulated

Controlled by ELCB

Controlled by MCB
50. As load on induction motor increases its power factor:
Remain constant

Goes on decreasing

Goes on increasing over after full load

Goes on increasing up to full load and then it falls again
51. During no load test of a 3 phase induction motor,the motor draws power:
For core loss and copper loss

For copper loss and windage-friction loss

For core loss and windage-friction loss

Only for every small copper loss
52. The recent method of smooth speed control of a three-phase induction motor over a wide range is:
Frequency control method

Rotor resistance control method

Voltage control method

None of the above methods
53. Rotor bars of squirrel cage rotor are sometimes skewed:
To prevent rotor from aligning and locking up with stator

To give more uniform torque

To reduce humming noise

Due to all above reasons
54. For 66 kV lines the number of insulator discs used is:
3

6

10

12
55. AC resistance of a line conductor is more than its DC resitance because of:
Skin effect

Proximity effect

Skin effect and proximity effect

None of these
56. What type of insulator will be used if the direction of the transmission line is changed?
Strain type

Shackle type

Pin type

Suspension type
57. The back emf set up in the armature of a synchronous motor depends on:
Rotor speed only

Rotor excitation only

Rotor excitation and rotor speed

Coupling angle,rotor speed and excitation
58. The current drawn by an over excited synchronous motor will be:
Depending on the nature of load

At lagging power factor

At leading power factor

At unity power factor
59. Two alternators are sharing an inductive load equally.What will be happened if the excitation of one alternator is increased?
Another alternator will deliver more current

Another alternator will deliver less current

Both will continue to share load equally

Both will deliver more current
60. A ceiling fan rotates slowly in either direction.The probable fault is:
An open in centrifugal switch

An open in capacitor

Short in the capacitor

Blown fuse
61. In repulsion motor, maximum torque is developed when:
Brush axis is at 180 degree electrical to the field axis

Brush axis is at 90 degree electrical to the field axis

Brush axis is at 45degree electrical to the field axis

Brush axis coincides with the field axis
62. Starting winding of a single phase motor of a refrigerator is disconnected from the circuit by means of a:
Centrifugal switch

Magnetic relay

Thermal relay

None of the above
63. How the speed control of universal motor used for sewing machine is done?
Introducing friction mecca-nism

Tapping the field at various point

Centrifugal mechanism

Introducing a variable resistance in series with the motor
64. Buchholz relay is operated by:
Gas pressure

Eddy current

Electrostatic induction

Electromagnetic induction
65. The size of earth wire is determined by:
The atmospheric condition

The voltage of the service wires

The current capacity of the service wires

None of these
66. Earthing in consumer premises is necessary to give protection against:
Overloading

Danger of electric shock

Voltage fluctuation

High temperature of the conductors
67. A single phase protection switch is used to protect:
The distribution transformer

The motor in case of fuse failure

The motor from the damage due to single phasing

From the maximum starting current of motor
68. The best location of the power factor improving device to be installed the transmission line is at:
The receiving end

The sending end

Middle of the line

Any place
69. --------motor has series characteristics
Capacitor start motor

Shaded pole motor

Repulsion motor

None of the above
70. How the light output is produced in electric discharge lamp?
By heating effect of current

By magnetic effect of current

By ionization in a gas or vapour

By cathode ray emission
71. Arc heating occurs when the air between electrodes of opposite polarity becomes:
Moistened

Dry

Ionized

None of the above
72. The meter used to measure the temperature of a furnace is:
Hydrometer

Pyrometer

Hygrometer

Tachometer
73. Which part is provided in a battery charger to prevent the flow of excessive curret into the battery?
Coarse selector

Tune selector switch

Limiting resistance

Transformer
74. What will happen to the filter circuit in battery charger if the output filter capacitor is opened?
Will not function

Will make humming noise

More current will flow

No output voltage
75. What are the two relative quantities to be plotted for external characteristics curve for DC shunt generator?
Field current Vs No load voltage

Armature current Vs Induced e.m.f

Load current Vs Terminal voltage

Load current Vs Induced e.m.f
76. What will happen to a self excited DC generator,if the generator runs in reverse direction?
The induced e.m.f.is increased

There is no change in the induced e.m.f

Spark will be produced in the commutator

Residual magnetism in the pole will be destroyed
77. Which is the application of delayed response type diazed fuse?
Motor circuits

Heating circuits

Lighting circuits

Electronic circuits
78. The force between two long parallel conductors is inversely proportional to:
Current in one conductor

Distance between the conductors

Radius of conductors

Product of current in two conductors
79. Which of the following circuit elements will oppose the change in the circuit current?
Inductance

Resistance

Capacitance

All of the above
80. The colour of light of mercury vapour lamp is:
Greenish blue

Yellow

Pink

White
81. South Africa was captured by Britain after the -----------war.
Opium war

Boer war

Boxer Rebellion

Carnatic war
82. The King of England during the American war of independence:
George IIIrd

George 1st

Henry VIII

Charles 1st
83. The classical dance form popular in the North-East parts of India:
Bihu

Chiraw

Manipuri

Kathak
84. The author of the famous book”Fidelio”:
T.S.Eliot

L.Beethoven

Lord Byron

George Bernard Shaw
85. The Headquarters of Economic and Social Commission for Asia and the Pacific(ESCAP)is at:
Jakarta

Manila

Kathmandu

Bangkok
86. Language in which maximum number of Newspapers are published?
Marathi

English

Hindi

Bengali
87. French official book:
Yellow book

White book

Green book

Blue book
88. The author of “Truth,Love and a Little Malice”:
Boris Pasternak

U.Thant

Amita Malik

Khushwant Singh
89. Who was the founder of Scientific Astronomy?
Hippalus

Hoffmann

Hippocrates

None of these
90. Who propounded the signs of the Zodiac?
Indians

Egyptians

Babylonians

None of these
91. A social Reformer of Kerala who started Atmavidhya Sangham was:
Vaikunda Swamikal

Brahmananda Sivayogi

Thycaud AyyaVaikunda

Vagbhadanandan
92. ”The Career and legend of Vasco da Gama”is a book written by:
Sanjay Subramaniyam

Arun Shourie

Kushwant Singh

None of these
93. Who among the foreign travellers made earliest reference regarding Kerala?
Marco Polo

Megasthanese

Ptolemy

Pliny
94. The Newspaper “Sujananadini”was started by:
C.V.Kunhiraman

C.Krishnan

Kesavan Asan

Sahodaran Ayyapan
95. Under 42nd amendment to our constitution the fundamental duties were enumerated.This concept of fundamental duties was borrowed from the constitution of:
USSR

Ireland

China

UK
96. The Rajya Sabha is a ------------body.
A part of the Lok Sabha

A temporary body

A permanent body

None of these
97. Article 368 deals with:
Special Provision for Jammu and Kashmir

President rule in a state

Pertains to the abolition of untouch ability

Amendment of the Constitution
98. ”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?
Raja Ram Mohan Roy

Dinbandhu Mitra

Jyothirao Phule

R.N.Tagore
99. Which of the following is one of the Harappan sites related to the maritime activities of the Harappan people?
Lothal

Kalibangan

Rangpur

Mohanjodaro
100. The cold current which meets with the warm gulf stream near Newfoundland?
Humboldt

Canaries

Benguala

Labrador