Deck 3: Thermal Conductivity, Welding, and Locomotives

Question 1

Which of the following has the highest value of thermal conductivity?

A)water
B)steam
C)solid ice
D)melting ice

Answer 1

solid ice

Question 2

The basic electrical requirement in arc welding is that there should be

A)coated electrodes
B)high open-circuit voltage
C)no arc blow
D)d.c. power supply.

Answer 2

high open-circuit voltage

Question 3

A.C. welding machine cannot be used for welding

A)mig
B)atomic hydrogen
C)resistance
D)submerged arc.

Answer 3

mig

Question 4

In electric welding, arc blow can be avoided by

A)using bare electrodes
B)welding away from earth ground connection
C)using a.c. welding machines
D)increasing arc length

Question 5

The major disadvantage of carbon arc welding is that

A)there is occurrence of blow holes
B)electrodes are consumed fast
C)separate filler rod is needed
D)bare electrodes are necessary.

Question 6

The free-running speed of a train does NOT depend on the

A)duration of stops
B)distance between stops
C)running time
D)acceleration.

Question 7

Longer coasting period for a train results in

A)higher acceleration
B)higher retardation
C)lower specific energy consumption
D)higher schedule speed.

Question 8

Skidding of a vehicle always occurs when

A)braking effort exceeds its adhesive weight
B)it negotiates a curve
C)it passes over points and crossings
D)brake is applied suddenly.

Question 9

In India diesel locomotives are manufactured at

A)ajmer
B)varanasi
C)bangalore
D)jamalpur

Question 10

The horsepower of steam locomotives is

A)upto 1500
B)1500 to 2000
C)2000 to 3000
D)3000 to 4000

Question 11

In tramways which of the following motors is used?

A)d.c. shunt motor
B)d.c. series motor
C)a.c. three phase motor
D)a.c. single phase capacitor start motor

Question 12

In a steam locomotive electric power is provided through

A)overhead wire
B)battery system
C)small turbo-generator
D)diesel engine generator

Question 13

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

A)steam engine
B)diesel engine
C)battery locomotive
D)any of the above

Question 14

In case of locomotives the tractive power is provided by

A)single cylinder double acting steam engine
B)double cylinder, single acting steam engine
C)double cylinder, double acting steam engine
D)single stage steam turbine

Question 15

which of the following track is electrified

A)delhi-bombay
B)delhi-madras
C)delhi-howrah
D)delhi-ahmedabad

Question 16

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

A)steam locomotives
B)diesel locomotives
C)electric locomotives
D)equal in all of the above

Question 17

For 600 V D.C. line for tramcars, brack is connected to

A)positive of the supply
B)negative of the supply
C)mid voltage of 300 v
D)none of the above

Question 18

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

A)main-line service
B)urban wervice
C)sub-urban service
D)all of the above

Question 19

The return circuit for tram cars is through

A)neutral wire
B)rails
C)cables
D)common earthing

Question 20

Fuse is a piece of wire of a materi

A)high melting point
B)low melting point
C)moderate melting point
D)none of the above

Question 21

Earthing is necessary to give protection against

A)electric shock
B)voltage fluctuation
C)overloading
D)high temperature of the conductors

Question 22

Static UPS requires                      

A)only rectifier
B)only inverter
C)both inverter and rectifier
D)none of the mentioned

Question 23

No discontinuity is observed in case of

A)short break static ups configuration
B)long break static ups configuration
C)no break static ups configuration
D)rotating type ups configuration

Question 24

Which is the material used to as anode in a lithium-ion battery?

A)brass foil coated with graphite
B)aluminum foil coated with graphite
C)copper foil coated with graphite
D)stainless steel coated with graphite

Question 25

What is the total number of cells present in a 12-volt battery?

A)5
B)6
C)3
D)4