1. The illumination level at A class stations should be [ d ]
(a) 20 lux
(b) 30 lux
(c) 40 lux
(d) 50 lux
Answer : (d) 50 lux
2. The illumination level at B class stations should be [ b ]
(a) 20 lux
(b) 30 lux
(c) 40 lux
(d) 50 lux
Answer : (b) 30 lux
3. The illumination level at C class stations should be [ a ]
(a) 20 lux
(b) 30 lux
(c) 40 lux
(d) 50 lux
Answer : (a) 20 lux
4. Recommended no. of light points in type I (DR) quarter is [ b ]
(a) 5
(b) 6
(c) 7
(d) 8
Answer : (b) 6
5 Recommended no. of light points in type II quarter is [ b ]
(a) 5
(b) 6
(c) 7
(d) 8
Answer : (b) 6
6 Recommended no. of light points in type III quarter is [ d ]
(a) 5
(b) 6
(c) 7
(d) 8
Answer : (d) 8
7 Recommended no. of light points in type IV quarter is [ c ]
(a) 8
(b) 9
(c) 10
(d) 11
Answer : (c) 10
8 Recommended no. of light points in type IV spl. quarter is [ c ]
(a) 11
(b) 12
(c) 13
(d) 14
Answer :(c) 13
9 Recommended no. of fan points in type I quarter is [ a ]
(a) 2
(b) 3
(c) 4
(d) 5
Answer :(a) 2
10 Recommended no. of fan points in type II quarter is [ a ]
(a) 2
(b) 3
(c) 4
(d) 5
Answer :(a) 2
11 Recommended no. of fan points in type III quarter is [ b ]
(a) 2
(b) 3
(c) 4
(d) 5
Answer : (b) 3
12 Recommended no. of fan points in type IV quarter is [ c ]
(a) 2
(b) 3
(c) 4
(d) 5
Answer : (c) 4
13 Recommended no. of fan points in type IV spl. quarter is [ d ]
(a) 2
(b) 3
(c) 4
d) 5
Answer : d) 5
14 Recommended connected load for type I (DR) quarter is [ a ]
(a) 1.36 kW
(b) 3.48 kW
(c) 4.17 kW
(d) 6.85 kW
Answer : (a) 1.36 kW
15 Recommended connected load for type II quarter is [ b ]
(a) 1.36 kW
(b) 3.48 kW
(c) 4.17 kW
(d) 6.85 kW
Answer : (b) 3.48 kW
16 Recommended connected load for type III quarter is [ c ]
(a) 1.36 kW
(b) 3.48 kW
(c) 4.17 kW
(d) 6.85 kW
Answer : (c) 4.17 kW
17 Recommended connected load for type IV quarter is [ d ]
(a) 1.36 kW
(b) 3.48 kW
(c) 4.17 kW
(d) 6.85 kW
Answer : (d) 6.85 kW
18 Recommended connected load for type IV spl. quarter is [ c ]
(a) 4.17 kW
(b) 6.85 kW
(c) 8.6 kW
(d) 11.85 kW
Answer :(c) 8.6 kW
19 Recommended connected load for type V quarter is [ d ]
(a) 4.17 kW
(b) 6.85 kW
(c) 8.6 kW
(d) 11.85 kW
Answer :(d) 11.85 kW
20. Luminous efficiency of a fluorescent tube is [ d ]
a. 10 lumens/ watt
b.20 lumens/ watt
c. 40 lumens/ watt
d. 60 lumens/ watt
Answer :d. 60 lumens/ watt
21. Candela is the unit of which of the following? [ b ]
a. wavelength
b. luminous intensity
c. luminous flux
d. frequency
Answer : b. luminous intensity
22. Colour of light depends upon [ c ]
a. frequency
b. wave length
c. both (a) and (b)
d. speed of light
Answer : c. both (a) and (b)
23. Illumination of one lumen per sq. metre is called ……… [ b ]
a. lumen metre
b. lux
c. foot candle
d. candela
Answer : b. lux
24. The unit of luminous flux is ………… [ b ]
a. watt/ m2
b. lumen
c. lumen/ m2
d. watt
Answer : b. lumen
25. Filament lamps operate normally at a power factor of [ c ]
a. 0.5 lagging
b. 0.8 lagging
c. unity
d. 0.8 leading
Answer :c. unity
26. What percentage of the input energy is radiated by filament lamps? [ a ]
a. 2 to 5 percent
b. 10 to 15 percent
c. 25 to 30 percent
d. 40 to 50 percent
Answer : a. 2 to 5 percent
27. The filament of a GLS lamp is made of [ a ]
a. tungsten
b. copper
c. carbon
d. aluminium
Answer : a. tungsten
28. Which of the following lamps is the cheapest for the same wattage? [ c ]
a. Fluorescent tube
b. mercury vapour lamp
c. GLS lamp
d. sodium vapour lamp
Answer : c. GLS lamp
29. Which of the following is not the standard rating of GLS lamps? [ b ]
a. 100 W
b. 75 W
c. 40 W
d. 15 W
Answer : b. 75 W
30. The colour of sodium vapour discharge lamp is [ c ]
a. red
b. pink
c. yellow
d. bluish green
Answer :c. yellow
31. A reflector is provided to [ d ]
a. protect the lamp
b. provide better illumination
c. avoid glare
d. do all of the above
Answer :d. do all of the above
32. The purpose of coating the fluorescent tube from inside with white power is [ d ]
a. to improve its life
b. to improve the appearance
c. to change the colour of light emitted to white
d. to increase the light radiations due to secondary emissions
Answer :d. to increase the light radiations due to secondary emissions
33. In the fluorescent tube circuit the function of choke is primarily to [ c ]
a. reduce the flicker
b. minimize the starting surge
c. initiate the arc and stabilize it
d. reduce the starting current
Answer :c. initiate the arc and stabilize it
34. The function of capacitor across the supply to the fluorescent tube is primarily to [ c ]
a. stabilize the arc
b. reduce the starting current
c. improve the supply power factor
d. reduce the noise
Answer :c. improve the supply power factor
35. Most affected parameter of a filament lamp due to voltage change is [ b ]
a. wattage
b. life
c. luminous efficiency
d. light output
Answer :b. life
36. In electric discharge lamps for stabilizing the arc [ c ]
a. a reactive choke is connected in series with the supply
b. a condenser is connected in series to the supply
c. a condenser is connected in parallel to the supply
d. a variable resistor is connected in the circuit
Answer : c. a condenser is connected in parallel to the supply
37. For precision work the illumination level required is of the order of [ a ]
a. 500 – 1000 lumens/m2
b. 200 – 400 lumens/m2
c. 50 – 100 lumens/ m2
d. 10 – 25 lumens/ m2
Answer : a. 500 – 1000 lumens/m2
38. For normal reading the illumination level required is around [ b ]
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
39. In electric discharge lamps light is produced by [ b ]
a. cathode ray emission
b. ionization in a gas or vapour
c. heating effect of current
d. magnetic effect of current
Answer : b. ionization in a gas or vapour
40. A substance which change its electrical resistance when illuminated by light is called [ c ]
a. photoelectric
b. photovoltaic
c. photo conductive
d. none of the above
Answer : c. photo conductive
41. In case of … power factor is the highest. [ a ]
a. GLS lamps
b. mercury arc lamps
c. tube lights
d. sodium vapour lamps
Answer : a. GLS lamps
42. A mercury vapour lamp gives … light. [ d ]
a. white
b. pink
c. yellow
d. greenish blue
Answer : d. greenish blue
43. Sometimes the wheels f rotating machinery, under the influence of fluorescent lamps appear to be stationary. This is due to the [ b ]
a. low power factor
b. stroboscopic effect
c. fluctuations
d. luminescence effect
Answer : b. stroboscopic effect
44. The flicker effect of fluorescent lamps is more pronounced at [ a ]
a. lower frequencies
b. higher frequencies
c. lower voltages
d. higher voltages
Answer : a. lower frequencies
45. Which gas can be filled in GLS lamp? [ d ]
a. oxygen
b. carbon di-oxide
c. xenon
d. any inert gas
Answer : d. any inert gas
46. The gas filled in vacuum filament lamps is [ d ]
a. nitrogen
b. argon
c. air
d. None
Answer : d. None
47. The vapour discharge tube used for domestic lighting has [ c ]
a. no filament
b. one filament
c. two filament
d. three filament
Answer : c. two filament
48. Stroboscopic effect due to use of discharge lamps in workshops results in moving machinery appearing [ d ]
a. stationary
b. stationary running slow
c. stationary running in reverse direction
d. all of the above
Answer : d. all of the above
49. Glare is reduced by [ d ]
a. using diffusers
b. increasing the height of the lamp
c. using reflectors to cut-off the light
d. all the above certain angle
Answer : d. all the above certain angle
50. Which of the following is present inside the fluorescent tube? [ c ]
a. argon and neon
b. argon and CO2
c. mercury vapour
d. helium and oxygen
Answer : c. mercury vapour
51. When an electric bulb is broken it produces bang; this is due to [ a ]
a. vacuum inside the bulb
b. pressure of air in the bulb
c. pressure inside is equal to that out-
d. none of the above side
Answer : a. vacuum inside the bulb
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