Electric Traction Model(1st)

An ideal traction system should have

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High starting tractive effort
All of the above
Easy speed control
Equipment capable of withstanding large temporary loads

The speed of a superfast train is

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60 kmph
More than 100 kmph
100 kmph
75 kmph

The efficiency of diesel locomotives is nearly

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20 to 25 percent
60 to 70 percent
30 to 40 percent
45 to 55 percent

Which of the following drives is suitable for mines where explosive gas exists?

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Battery locomotive
Any of the above
Diesel engine
Steam engine

Which of the following is the advantage of electric braking?

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It is instantaneous
It avoids wear of track
Motor continues to remain loaded during braking
More heat is generated during braking

Speed-time curve of main line service differs from those of urban and suburban services on following account

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It has longer coasting period
It has longer free running period
All of the above
Accelerating and braking periods are comparatively smaller

_________ frequency is not common in low frequency traction system

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16 Hz
40 Hz
25 Hz
None of these

Specific energy consumption becomes

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Less if distance between stops is more
More on steeper gradient
All of the above
More with high train resistance

The coasting retardation is around

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1.6 km phps
40 km phps
0.16 km phps
16 km phps

In case of a steam engine an average coal consumption per km is nearly

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28 to 30 kg
60 to 80 kg
150 to 175 kg
100 to 120 kg

Specific energy consumption is least in _______ service.

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Main line
None of these
Main line
Suburban

Which of the following state capitals (in India) is not on broad gauge track?

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Bhopal
Chandigarh
Lucknow
Jaipur

In case of steam engines the steam pressure is

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5 to 8 kgf/cm²
1 to 4 kgf/cm²
25 to 35 kgf/cm²
10 to 15 kgf/cm²

In case of ___________ free running and coasting periods are generally long.

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All of the above
Suburban service
Urban service
Mainline service

Locomotives with monometer bogies have

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Suitability for passenger as well as freight service
Uneven distribution of tractive effect
Low coefficient of adhesion
Lot of skidding

Main traction systems used in India are, those using

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All of the above
Steam engine locomotives
Electric locomotives
Diesel engine locomotives

The rate of acceleration on sub-urban or urban services is restricted by the consideration of

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Engine power
Passenger Discomfort
Track curves
Track size

The rate of acceleration on suburban or urban service is in the range

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5 to 10 km phps
0.2 to 0.5 km phps
1.6 to 4.0 km phps
15 to 25 km phps

If the coefficient of adhesion on dry rails is 0.26, which of the following could be the value for wet rails?

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0.16
0.3
0.225
0.26

Battery operated trucks are used in

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Narrow gauge traction
Steel mills
Factories for material transportation
Power stations

Coefficient of adhesion is

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Low in case of D.C. traction than in the case of AC. traction
Any of the above
High in case of D.C. traction than in the case of AC. traction
Equal in both AC. and D.C. traction

Quadrilateral speed-time curve pertains to which of the following services?

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Main line service
Urban service
Urban and suburban service
Suburban service

Which of the following is the disadvantage of electric traction over other systems of traction?

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Short time power failure interrupts traffic for hours
Corrosion problems in the underground pipe work
Interference with communication lines
High capital outlay in fixed installations beside route limitation

In a steam locomotive electric power is provided through

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Overhead wire
Battery system
Small turbo-generator
Diesel engine generator

The overall efficiency of steam locomotive is around

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25 to 35 percent
15 to 20 percent
35 to 45 percent
5 to 10 percent

Locomotive having mono-motor bogies

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Are suited both for passenger as well as freight service
Has better riding qualities due to the reduction of lateral forces
Has better coefficient of adhesion
Has all above qualities

Suri transmission is

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Electrical pneumatic
Mechanical electrical
Hydro mechanical
Hydro pneumatic

Watt-hours per tonne km is usually the specific energy consumption for suburban services.

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120 - 150
160 - 200
15 - 20
50 - 75

The wheels of a train, engine as well as bogies, are slightly tapered to

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Increase friction
Facilitate in taking turns
Facilitate braking
Reduce friction

For which of the following locomotives the maintenance requirements are the least?

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Diesel locomotives
Steam locomotives
Equal in all of the above
Electric locomotives

Coefficient of adhesion reduces due to the presence of which of the following?

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Dew on rails
Sand on rails
Oil on the rails
Both (B) and (C)

Tractive effort is required to

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Overcome the gravity component of train mass
Accelerate the train mass
Overcome friction, windage and curve resistance
Do all of the above

The value of coefficient of adhesion will be high when rails are

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Wet
Sprayed with oil
Greased
Cleaned with sand

Which of the following braking systems on the locomotives is costly?

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Vacuum braking on diesel locomotives
Vacuum braking on steam locomotives
All braking systems are equally costly
Regenerative braking on electric locomotives

For three-phase induction motors which of the following is the least efficient method of speed control?

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Rheostat control
Combination of cascade and pole changing
Pole changing
Cascade control

The specific energy consumption of a train depends on which of the following?

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Gradient
All of the above
Distance covered
Acceleration and retardation

Overhead lines for power supply to tram cars are at a minimum height of

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3 m
15 m
10 m
6 m

Overload capacity of diesel engines is usually restricted to

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20 percent
2 percent
10 percent
40 percent

Automatic signaling is used for which of the following trains?

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All trains
Suburban and Urban electric trains
Mail and express trains
Superfast trains

Series motor is not suited for traction duty due to which of the following account?

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Current surges after temporary switching off supply
Less current drain on the heavy load torque
Commutating property at heavy load
Self relieving property

Electric locomotives in India are manufactured at

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Chittaranjan
Jamalpur
Bangalore
Gorakhpur

________ have maximum unbalanced forces

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Diesel locomotives
Electric locomotives
Steam locomotives
Diesel saunters

The friction at the track is proportional to

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Speed
1/speed
None of the above
1/(speed)²

Long distance railways use which of the following?

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25 kV two phase A.C.
200 V D.C.
25 kV single phase A.C.
25 kV three phase A.C.

The resistance encountered by a train in motion is on account of

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Resistance offered by air
All of the above
Friction at the track
Friction at various parts of the rolling stock

Automatic signalling is used for which of the following trains ?

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Suburban and Urban electric trains
All trains
Mail and express trains
Superfast trains

In India, electrification of railway track was done for the first time in which of the following years?

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1880 - 1885
1947 - 1954
1820 - 1825
1925 - 1932

Due to which of the following coefficient of adhesion improves?

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All of the above
Rust on the rails
Sand on the rails
Dust on the rails

The steam engine provided on steam locomotives is

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Single acting condensing type
Double acting non-condensing type
Double acting condensing type
Single acting non-condensing type

For given maximum axle load tractive efforts of AC. locomotive will be

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Equal to that of D.C. locomotive
More than that of D.C. locomotive
Less than that of D.C. locomotive
None of the above

Methods can bring the locomotive to dead stop.

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Rheostat braking
Regenerative braking
None of the above
Plugging braking

In tram ways which of the following motors is used?

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D.C. shunt motor
D.C. series motor
A.C. three phase motor
AC. single phase capacitor start motor

Specific energy consumption is affected by which of the following factors?

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Gradient
All of the above
Retardation and acceleration values
Distance between stops

The return circuit for tram cars is through

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Rails
Common earthing
Cables
Neutral wire

In India diesel locomotives are manufactured at

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Ajmer
Bangalore
Jamalpur
Varanasi

The normal value of adhesion friction is

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0.75
0.40
0.12
0.25

Which of the following methods is used to control speed of 25 kV, 50 Hz single phase traction?

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Series parallel operation of motors
Reduced current method
Tap changing control of transformer
All of the above

_______ was the first city in India to adopt electric traction.

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Delhi
Bombay (Mumbai)
Calcutta (kolkata)
Madras (Chennai)

The horsepower of steam locomotives is

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1500 to 2000
Up to 1500
2000 to 3000
3000 to 4000

Which of the following happens in Kando system?

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None of the above
Three phase A.C. is converted into D.C.
Single phase A.C. is converted into D.C.
Single phase supply is converted into three phase system

The number of passenger coaches that can be attached to a diesel engine locomotive on broad gauge is usually restricted to

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14
10
17
5

Which of the following state capitals is not on broad gauge track ?

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Bhopal
Chandigarh
Jaipur
Lucknow

For diesel locomotives the range of horsepower is

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500 to 1000
50 to 200
3000 to 5000
1500 to 2500

The pulsating torque exerted by steam locomotives causes which of the following?

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Jolting and skidding
Hammer blow
Pitching
All of the above

The braking retardation is usually in the range

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3 to 5 km phps
0.15 to 0.30 km phps
0.6 to 2.4 km phps
0.30 to 0.6 km phps

When a bogie negotiates a curve, reduction in adhesion occurs resulting in sliding. Thus sliding is acute when

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Wheel base of axles is more
Degree of curvature is more
Both (A) and (B)
None of the above

In case of locomotives the tractive power is provided by

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Single cylinder double acting steam engine
Double cylinder, single acting steam engine
Double cylinder, double acting steam engine
Single stage steam turbine

_________ locomotive has the highest operational availability.

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All of the above
Diesel
Steam
Electric

Energy consumption in propelling the train is required for which of the following?

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All of the above
Acceleration
Work against the resistance to motion
Work against gravity while moving up the gradient

The air resistance to the movement of the train is proportional to

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(speed)²
1/speed
(speed)
speed

Which of the following braking systems is used on steam locomotives?

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Pneumatic system
None of the above
Hydraulic system
Vacuum system

Which of the following is the voltage for single phase A.C. system?

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22 V
5 kV
440 V
15 kV

Vacuum is created by which of the following?

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None of the above
Any of the above
Ejector
Vacuum pump

For 25 kV single phase system power supply frequency is

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50 Hz
25 Hz
60 Hz
16 Hz

Which of the following is an advantage of electric traction over other methods of traction?

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Faster acceleration
All of the above
No pollution problems
Better braking action

The voltage used for suburban trains in D.C. system is usually

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12 V
24 V
600 to 750 V
220 V

In main line service as compared to urban and suburban service

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Acceleration and retardation rates are low
All of the above
Distance between the stops is more
Maximum speed reached is high

The speed of a locomotive is controlled by

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Applying brakes
Flywheel
Regulating steam flow to engine
Gear box

Power for lighting in passenger coach, in a long distance electric train, is provided

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Through individual generator of bogie and batteries
Through locomotive
Directly through overhead electric line
Through rails

Electric Traction Model(1st) : Question 1 of 79