McqMate
1. |
Which of the following instruments is used for the comparison of candle powers of different sources? |
A. | radiometer |
B. | bunsen meter |
C. | photometer |
D. | candle meter |
Answer» C. photometer |
2. |
The illumination at various points on a horizontal surface illuminated by the same source varies as |
A. | cos3θ |
B. | cos θ |
C. | 1/r2 |
D. | cos2θ. |
Answer» A. cos3θ |
3. |
Floodlighting is NOT used for purposes. |
A. | reading |
B. | aesthetic |
C. | advertising |
D. | industrial. |
Answer» A. reading |
4. |
Which of the following lamp has minimum initial cost of installation but maximum running cost ? |
A. | incandescent |
B. | fluorescent |
C. | mercury vapour |
D. | sodium vapour. |
Answer» A. incandescent |
5. |
Candela is the unit of which of the following? |
A. | wavelength |
B. | luminous intensity |
C. | luminous flux |
D. | frequency |
Answer» B. luminous intensity |
6. |
Colour of light depends upon |
A. | frequency |
B. | wave length |
C. | both (a) and (b) |
D. | speed of light |
Answer» C. both (a) and (b) |
7. |
Illumination of one lumen per sq. metre is called |
A. | lumen metre |
B. | lux |
C. | foot candle |
D. | candela |
Answer» B. lux |
8. |
A solid angle is expressed in terms of |
A. | radians/metre |
B. | radians |
C. | steradians |
D. | degrees |
Answer» C. steradians |
9. |
The unit of luminous flux is . |
A. | watt/m2 |
B. | lumen |
C. | lumen/m2 |
D. | watt |
Answer» B. lumen |
10. |
Filament lamps operate normally at a power factor of |
A. | 0.5 lagging |
B. | 0.8 lagging |
C. | unity |
D. | 0.8 leading |
Answer» C. unity |
11. |
The filament of a GLS lamp is made of |
A. | tungsten |
B. | copper |
C. | carbon |
D. | aluminium |
Answer» A. tungsten |
12. |
Which of the following lamps is the cheapest for the same wattage? |
A. | fluorescent tube |
B. | mercury vapour lamp |
C. | gls lamp |
D. | sodium vapour lamp |
Answer» C. gls lamp |
13. |
On which of the following factors dies the depreciation or maintenance factor depend? |
A. | lamp cleaning schedule |
B. | ageing of the lamp |
C. | type of work carried out at the premises |
D. | all of the above factors |
Answer» D. all of the above factors |
14. |
For the same lumen output, the running cost of the fluorescent lamp is |
A. | equal to that of filament lamp |
B. | less than that of filament lamp |
C. | more than that of filament lamp |
D. | any of the above |
Answer» B. less than that of filament lamp |
15. |
The flicker effect of fluorescent lamps is more pronounced at |
A. | lower frequencies |
B. | higher frequencies |
C. | lower voltages |
D. | higher voltages |
Answer» A. lower frequencies |
16. |
...... is a cold cathode lamp. |
A. | fluorescent lamp |
B. | neon lamp |
C. | mercury vapour lamp |
D. | sodium vapour lamp |
Answer» B. neon lamp |
17. |
For normal reading the illumination level required is around |
A. | 20-40 lumens/m2 |
B. | 60-100 lumens/m2 |
C. | 200-300 lumens/m2 |
D. | 400-500 lumens/m2 |
Answer» B. 60-100 lumens/m2 |
18. |
Which gas can be filled in GLS lamps? |
A. | oxygen |
B. | carbon dioxide |
C. | xenon |
D. | any inert gas |
Answer» D. any inert gas |
19. |
Which of the following is not the type of refrigerant? |
A. | organic refrigerants |
B. | inorganic refrigerants |
C. | azeotrope refrigerants |
D. | halo-helium refrigerants |
Answer» D. halo-helium refrigerants |
20. |
The refrigerants which are first cooled by refrigerants and then used for cooling purposes are known as refrigerants. |
A. | secondary, primary |
B. | primary, secondary |
C. | tertiary, primary |
D. | secondary, tertiary |
Answer» B. primary, secondary |
21. |
Which one of the following inorganic refrigerants is often used? |
A. | nh3 |
B. | co2 |
C. | h2o |
D. | so2 |
Answer» A. nh3 |
22. |
From the following refrigerants, which is one of the most stable refrigerants? |
A. | ammonia |
B. | r – 12 |
C. | carbon dioxide |
D. | sulphur dioxide |
Answer» D. sulphur dioxide |
23. |
In the presence of which of the following, Sulphur dioxide becomes corrosive? |
A. | r – 12 |
B. | ammonia |
C. | water |
D. | carbon dioxide |
Answer» C. water |
24. |
is widely used in large industrial plants such as cold storages and ice plants as per the cost basis. |
A. | r – 40 |
B. | r – 717 |
C. | r – 744 |
D. | r – 764 |
Answer» B. r – 717 |
25. |
Where is the reciprocating compressor mostly suitable? |
A. | small displacements and low condensing pressures |
B. | small displacements and high condensing pressures |
C. | large displacements and low condensing pressures |
D. | large displacements and high condensing pressures |
Answer» B. small displacements and high condensing pressures |
26. |
Which of the following is the condition to use two compressors in the refrigeration system? |
A. | the desired temperature is 3°c |
B. | the desired temperature is -3°c |
C. | the desired temperature is -50°c |
D. | the desired temperature is -5°c |
Answer» C. the desired temperature is -50°c |
27. |
Centrifugal compressors are used to handle volume of refrigerant. |
A. | small |
B. | medium |
C. | large |
D. | very large |
Answer» C. large |
28. |
Which of the following cooling towers possess maximum heat transfer from air to water? |
A. | natural draft |
B. | mechanical draft |
C. | natural and mechanical draft |
D. | atmospheric draft |
Answer» B. mechanical draft |
29. |
Which of the following is true about the optimum effective temperature for human comfort? |
A. | same in winter and summer |
B. | not dependent on season |
C. | lower in winter than in summer |
D. | higher in winter than in summer |
Answer» C. lower in winter than in summer |
30. |
When the heat stored in the body is the human body feels comfortable. |
A. | zero |
B. | infinite |
C. | positive |
D. | negative |
Answer» A. zero |
31. |
Room air conditioners and packaged units are examples of |
A. | direct expansion systems |
B. | indirect expansion systems |
C. | chilled water systems |
D. | indirect contraction systems |
Answer» A. direct expansion systems |
32. |
Which of the following types of filters used in the air conditioning system is made of cloth that is discarded on getting dirty? |
A. | viscous type filters |
B. | dry filter |
C. | spray washers |
D. | electric precipitators |
Answer» B. dry filter |
33. |
The process of extraction of the certain required amount of water from air is known as |
A. | heating |
B. | cooling |
C. | humidification |
D. | dehumidification |
Answer» D. dehumidification |
34. |
Which of the following is capable of absorbing excess moisture from the air? |
A. | silica gel |
B. | charcoal |
C. | salts of calcium or ammonia |
D. | activated alumina |
Answer» C. salts of calcium or ammonia |
35. |
Magnetic materials are heated with the help of |
A. | hysteresis loss |
B. | electric arc |
C. | electric current |
D. | radiation. |
Answer» A. hysteresis loss |
36. |
In the indirect resistance heating method, heat is delivered to the charge |
A. | direcly |
B. | by radiation |
C. | by convection |
D. | both (b) and (c). |
Answer» D. both (b) and (c). |
37. |
Electric ovens using heating elements of........................... can produce temperatures up to 3000°C |
A. | nickel |
B. | graphite |
C. | chromium |
D. | iron. |
Answer» B. graphite |
38. |
Which of the following heating method is based on the transformer principle ? |
A. | resistance heating |
B. | eddy-current heating |
C. | induction heating |
D. | dielectric heating. |
Answer» C. induction heating |
39. |
Which of the following furnace suffers from pinch effect? |
A. | resistance furnace |
B. | core type induction furnace |
C. | coreless induction furnace |
D. | vertical core type induction furnace. |
Answer» B. core type induction furnace |
40. |
The coreless induction furnace uses high-frequency electric supply in order to obtain high |
A. | flux density |
B. | eddy-current loss |
C. | primary resistance |
D. | power factor. |
Answer» B. eddy-current loss |
41. |
Spot welding is used for |
A. | thin metal sheets |
B. | rough and irregular surfaces |
C. | costings only |
D. | thick sections |
Answer» A. thin metal sheets |
42. |
Which of the following is an advantages of heating by electricity? |
A. | quicker operation |
B. | higher efficiency |
C. | absence of flue gases |
D. | all of the above |
Answer» B. higher efficiency |
43. |
...... has the highest value of thermal conductivity. |
A. | copper |
B. | aluminium |
C. | brass |
D. | steel |
Answer» A. copper |
44. |
...... method has leading power factor |
A. | resistance heating |
B. | dielectric heating |
C. | arc heating |
D. | induction heating |
Answer» B. dielectric heating |
45. |
Which of the following methods of heating is not dependent on the frequency of supply? |
A. | induction heating |
B. | dielectric heating |
C. | electric resistance heating |
D. | all of the above |
Answer» C. electric resistance heating |
46. |
When a body reflects entire radiation incident on it, then it is known as |
A. | white body |
B. | grey body |
C. | black body |
D. | transparent body |
Answer» A. white body |
47. |
For the transmission of heat from one body to another |
A. | temperature of the two bodies must be different |
B. | both bodies must be solids |
C. | both bodies must be in contact |
D. | at least one of the bodies must have some source of heating |
Answer» A. temperature of the two bodies must be different |
48. |
A perfect black body is one that |
A. | transmits all incident radiations |
B. | absorbs all incident radions |
C. | reflects all incident radiations |
D. | absorbs, reflects and transmits all incident radiations |
Answer» B. absorbs all incident radions |
49. |
Heat is transferred simultaneously by condition, convection and radiation |
A. | inside boiler furnaces |
B. | during melting of ice |
C. | through the surface of the insulted pipe caring steam |
D. | from refrigerator coils to freezer of a refrigerator |
Answer» A. inside boiler furnaces |
50. |
The process of heat transfer during the re-entry of satellites and missiles, at very high speeds, into earth’s atmosphere is known as |
A. | ablation |
B. | radiation |
C. | viscous dissipation |
D. | irradiation |
Answer» A. ablation |
51. |
Which of the following has the highest value of thermal conductivity? |
A. | water |
B. | steam |
C. | solid ice |
D. | melting ice |
Answer» C. solid ice |
52. |
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» B. high open-circuit voltage |
53. |
A.C. welding machine cannot be used for welding |
A. | mig |
B. | atomic hydrogen |
C. | resistance |
D. | submerged arc. |
Answer» A. mig |
54. |
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 |
Answer» C. using a.c. welding machines |
55. |
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. |
Answer» A. there is occurrence of blow holes |
56. |
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. |
Answer» A. duration of stops |
57. |
Longer coasting period for a train results in |
A. | higher acceleration |
B. | higher retardation |
C. | lower specific energy consumption |
D. | higher schedule speed. |
Answer» C. lower specific energy consumption |
58. |
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. |
Answer» A. braking effort exceeds its adhesive weight |
59. |
In India diesel locomotives are manufactured at |
A. | ajmer |
B. | varanasi |
C. | bangalore |
D. | jamalpur |
Answer» B. varanasi |
60. |
The horsepower of steam locomotives is |
A. | upto 1500 |
B. | 1500 to 2000 |
C. | 2000 to 3000 |
D. | 3000 to 4000 |
Answer» B. 1500 to 2000 |
61. |
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 |
Answer» B. d.c. series motor |
62. |
In a steam locomotive electric power is provided through |
A. | overhead wire |
B. | battery system |
C. | small turbo-generator |
D. | diesel engine generator |
Answer» C. small turbo-generator |
63. |
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 |
Answer» C. battery locomotive |
64. |
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 |
Answer» C. double cylinder, double acting steam engine |
65. |
which of the following track is electrified |
A. | delhi-bombay |
B. | delhi-madras |
C. | delhi-howrah |
D. | delhi-ahmedabad |
Answer» C. delhi-howrah |
66. |
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 |
Answer» C. electric locomotives |
67. |
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 |
Answer» B. negative of the supply |
68. |
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 |
Answer» A. main-line service |
69. |
The return circuit for tram cars is through |
A. | neutral wire |
B. | rails |
C. | cables |
D. | common earthing |
Answer» B. rails |
70. |
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 |
Answer» B. low melting point |
71. |
Earthing is necessary to give protection against |
A. | electric shock |
B. | voltage fluctuation |
C. | overloading |
D. | high temperature of the conductors |
Answer» A. electric shock |
72. |
Static UPS requires |
A. | only rectifier |
B. | only inverter |
C. | both inverter and rectifier |
D. | none of the mentioned |
Answer» C. both inverter and rectifier |
73. |
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 |
Answer» C. no break static ups configuration |
74. |
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 |
Answer» B. aluminum foil coated with graphite |
75. |
What is the total number of cells present in a 12-volt battery? |
A. | 5 |
B. | 6 |
C. | 3 |
D. | 4 |
Answer» B. 6 |
76. |
Which of the following decreases within turn decreases the charging rate? |
A. | temperature |
B. | pressure |
C. | enthalpy |
D. | entropy |
Answer» A. temperature |
77. |
Which of the following causes the corrosion of terminals and clamps? |
A. | spilled electrolyte |
B. | increase in temperature |
C. | decrease in pressure |
D. | due to high current |
Answer» A. spilled electrolyte |
78. |
Grounding transformer is used where neutral .........available |
A. | is |
B. | is not |
C. | either a or b |
D. | . none of the above |
Answer» B. is not |
79. |
In equipment grounding, the enclosure is connected to ...........wire |
A. | ground |
B. | neutral |
C. | phase |
D. | either a or b |
Answer» A. ground |
80. |
Earthing is necessary to give protection against |
A. | danger of electric shock |
B. | voltage fluctuation |
C. | overloading |
D. | high temperature of the conductors |
Answer» A. danger of electric shock |
81. |
In case of earth fault, the underground neutral system lead to arcing ground |
A. | does |
B. | does not |
C. | any of above |
D. | none of above |
Answer» A. does |
82. |
The advantage of neutral earthing |
A. | safety of personnel |
B. | reduction of earth fault current |
C. | elimination of arcing ground |
D. | none of the above |
Answer» C. elimination of arcing ground |
83. |
In a substation the equipment used to limit short circuit current level is |
A. | series reactor |
B. | coupling capacitor |
C. | lightening switch |
D. | isolator. |
Answer» A. series reactor |
84. |
In a star connected system without neutral grounding, zero sequence currents are |
A. | zero |
B. | phaser sum of phase currents |
C. | same as rms value of phase currents |
D. | same as peak value of phase currents |
Answer» A. zero |
85. |
Grounding transformer is used where neutral available |
A. | is |
B. | is not |
C. | any of above |
D. | none of above |
Answer» B. is not |
86. |
Ground resistance value for sensitive installations is |
A. | less than 5 Ω |
B. | more than 5 Ω |
C. | equal to 50 Ω |
D. | any of above |
Answer» A. less than 5 Ω |
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