MCQ in Illumination Part 1 | REE Board Exam

This is the Multiple Choice Questions Part 1 of the Series in Illumination as one of the Electrical Engineering topic. In Preparation for the REE Board Exam make sure to expose yourself and familiarize in each and every questions compiled here taken from various sources including but not limited to past Board Exam Questions in Electrical Engineering field, Electrical Engineering Books, Journals and other Electrical Engineering References.

Start Practice Exam Test Questions Part 1 of the Series

1. EE Board Exam April 1992

A piece of paper lies on a table 2 m away from a point directly below a bulb of 100 cd and is 4 m above the table. Calculate the illumination on the center of the paper in lux.

A. 5.2

B. 5.7

C. 4.5

D. 3.4

2. EE Board Exam April 1989

A medium unshaded lamp hangs 8 m directly above the table. To what distance should it be lowered to increase the illumination to 4.45 times its former value?

A. 4.02 m

B. 3.86 m

C. 3.79 m

D. 4.21 m

3. EE Board Exam April 1994

A floodlight emitting 25,000 candelas in the center of its beam is aimed at 60° to a point on the ground 20 meters away. The illumination of the point in lux is

A. 54.12

B. 62.5

C. 31.25

D. 625

4. EE Board Exam April 1985

A light is to be placed on a wall in order to obtain maximum brightness of illumination. To achieve this brightness, how high on the wall should this light bulb be placed to a point on the floor that is 3.6 m from the wall?

A. 2.54 m

B. 2.25 m

C. 2.08 m

D. 2.86 m

5. EE Board Exam October 1991

A lamp of 500 cd is placed at the center of a room, 20 m x 10 m x 5 m. Calculate the illumination in each corner of the floor.

A. 0.83 lux

B. 0.81 lux

C. 0.78 lux

D. 0.98 lux

6. EE Board Exam October 1991

A lamp of 500 cd power is placed at the center of a room, 20 m x 10 m x 6 m. Calculate the illumination in a point in the middle of a 10 m wall at a height of 2 m from the floor.

A. 4.75 lux

B. 4.98 lux

C. 4.69 lux

D. 4.88 lux

7. EE Board Exam October 1992

Luminaires of 2000 lumens output will be installed in a room. The desired illumination is 200 foot-candle. The coefficient of utilization is 0.45 and maintenance factor is 90%. Determine the number of luminaires needed if the size of the room is 120 m².

A. 30

B. 28

C. 32

D. 36

8. EE Board Exam October 1993

A hall 35 m x 20 m is to be provided with a general illumination of 130 lux. If the depreciation factor is 1.4 and the coefficient of utilization is 0.50, determine the number of fluorescent lamp required. Assume luminous efficiency of the fluorescent tube as 50 lumens per watt for 80-watt lamp.

A. 62 lamps

B. 65 lamps

C. 63 lamps

D. 64 lamps

9. EE Board Exam April 1990

A hall 30 m long and 12 m wide is to be illuminated and the illumination required is 50 meter-candles. Calculate the number of lamps required taking a depreciation factor of 1.3 and utilization coefficient of 0.5 given that the output of the lamp to be used is rated 100 W, 1615 lumens.

A. 30

B. 29

C. 28

D. 27

10. EE Board Exam April 1993

A room 20 m x 10 m is to be illuminated by eight lamps and the average illumination is to be 50 lumens per meter. If the utilization factor is 0.48 and depreciation factor 1.2, calculate the mean spherical power per lamp.

A. 249 cp

B. 255 cp

C. 235 cp

D. 224 cp

11. EE Board Exam October 1991

It is required to provide illumination of 150 meter candle in a factory hall 45 m x 15 m. Assume that the depreciation factor is 0.80, coefficient of utilization is 0.40 and efficiency of the lamp is 20 lumens per watt. Calculate the number of 250 W lamps.

A. 60

B. 62

C. 63

D. 61

12. EE Board Exam March 1998, September 2000

The illumination of a room is being designed. The data are as follows:

Room length = 30 ft

Room width = 20 ft

Coefficient of utilization = 0.6

Maintenance factor = 70%

Required foot-candle = 50

Lumens per lamp = 3300

Watts per lamp = 53

Voltage = 220 V

Power factor = 75%

What is the total current of the lamp required to satisfy the requirements?

A. 21 A

B. 15 A

C. 7 A

D. 25 A

13. EE Board Exam October 1989

The floor area of a room is 10 meters by 10 meters. The desired illumination level is 150 lux. Assume the coefficient of utilization is 0.51, the maintenance factor is 0.95 and in the market a fluorescent luminaire provide 1200 lumens output of light. Determine the number of luminaires needed for the room.

A. 24 lamps

B. 28 lamps

C. 25 lamps

D. 26 lamps

14. REE Board Exam September 2001

The illumination of a room having dimensions of 20 x 10 sq ft is 50 fc. Find the luminous flux if the maintenance factor is 70% and the illumination factor is 0.60.

A. 35,760

B. 15,150

C. 23,810

D. 20,345

15. REE Board Exam April 1997

Which of the following affect the overall efficiency of a lighting installation?

A. age of lamp

B. dust and dirt

C. voltage

D. all of these

16. REE Board Exam April 1995

The rate of passage of radiant energy evaluated by reference to the luminous sensation produced by it is called

A. luminous flux

B. luminous radiation

C. luminous plane

D. luminosity

17. EE Board Exam April 1993

An instrument used to measure the intensity of a light source

A. illumination meter

B. Bensen photometer

C. cygnometer

D. candle meter

18. REE Board Exam April 1993, April 1992

The ratio of lumens reaching the work plane divided by the total lumens generated by the light is

A. room ratio

B. coefficient of utilization

C. illumination factor

D. maintenance factor

19. REE Board Exam September 2004

A light source has an illumination of 100 footcandles (fc), what is the illumination in lux?

A. 1,204

B. 1,075

C. 1,496

D. 1,360

20. REE Board Exam April 2004

A room with dimensions of 72 ft x 36 ft x 13 ft requires 50 footcandles, maintenance factor of 0.7, coefficient of utilization of 0.46 and RI of 4. Calculate the required lumens output of the lamps.

A. 144,000

B. 136,800

C. 402,485

D. 74,690

21. REE Board Exam September 2001

The illumination of a room is being designed. The illumination intensity required is 50 footcandles. The maintenance factor is 70% and coefficient of utilization is 0.6. If the room is 20 ft by 15 ft, what is the total required lumens output of the lamp?

A. 35,000 lumens

B. 10,050 lumens

C. 6,300 lumens

D. 12,800 lumens

22. REE Board Exam September 2001

A 40 ft by 20 ft office is to be illuminated with duplex fluorescent luminaires at a level of 50 footcandles. The maintenance factor and coefficient of utilization are estimated to be 70% and 60%, respectively. Each fluorescent produces 3,300 lumens. How many luminaires are required?

A. 18

B. 8

C. 14

D. 28

23. Candela is the unit of

A. flux

B. luminous intensity

C. illumination

D. luminance

24. The unit of illuminance is

A. lumen

B. cd/m²

C. lux

D. steradian

25. The illumination at various points on a horizontal surface illuminated by the same source varies as

A. cos³ θ

B. cos θ

C. 1/r²

D. cos² θ

26. The M.S.C.P. Of a lamp which gives out a total luminous flux of 400 π lumen is ______ candela.

A. 200

B. 100

C. 50

D. 400

27. A perfect diffuser surface is one that

A. diffuses all the incident light

B. absorbs all the incident light

C. transmits all the incident light

D. scatters light uniformly in all directions

28. The direct lighting scheme is most efficient but is liable to cause

A. monotony

B. glare

C. hard shadows

D. both B and C

29. Total flux required in any lighting scheme depends inversely on

A. illumination

B. surface area

C. utilization factor

D. space/height ratio

30. Flood lighting is NOT used for ______ purposes.

A. reading

B. aesthetic

C. advertising

D. industrial

31. Which of the following lamp has minimum initial cost of installation but maximum running cost?

A. incandescent

B. fluorescent

C. mercury vapor

D. sodium vapor

32. An incandescent lamp can be used

A. in any position

B. on both ac & dc supply

C. for street lighting

D. all of these

33. The average working life of a fluorescent lamp is about _____ hours.

A. 1000

B. 4000

C. 3000

D. 5000

34. The luminous efficiency of a sodium vapor lamp is about ____ lumen/watt.

A. 10

B. 30

C. 50

D. 70

35. A room measuring 40 ft by 80 ft is to be illuminated by fluorescent lamps arranged in 16 rows. Each fixture has 2 fluorescent lamps having an output of 3300 lumens per lamp. The maintenance factor and utilization factor are 0.65 and 0.75 respectively. If the required illumination is 60 cp, calculate the number of fixtures required.

A. 120

B. 80

C. 60

D. 150

36. A room measuring 40 ft by 80 ft is to be illuminated by fluorescent lamps having an output of 3300 lumens per lamp arranged in 4 rows. The maintenance factor and utilization factor are 0.7 and 0.6 respectively. If the required illumination is 60 cp, calculate the number of fixtures required in each row.

A. 70 lamps per row

B. 140 lamps per row

C. 35 lamps per row

D. 40 lamps per row

37. The floor area of a room is 10 meters by 10 meters. The desired illumination level is 150 ftcandle. Assume the coefficient of utilization is 0.51, the maintenance factor of 0.95 and in the market a fluorescent luminaire provides 1,200 lumens output of light. Design the number of luminaries needed for the room.

A. 198

B. 278

C. 365

D. 154

38. Two lamps are placed 100 m apart. Lamp A and lamp B have luminous intensity of 150 and 450 candelas respectively. Lamp A is placed 15 m above the ground while lamp B is placed 20 m above of the same level. What is the illumination at the center of the lamp posts at ground level?

A. 0.016

B. 0.07

C. 0.06

D. 0.04

39. A measure of the lumen output per watt input produced by the light source.

A. Lumen

B. Efficacy

C. Coefficient of utilization

D. Quality factor

40. Carbon arc lamps are commonly used in

A.         Cinema Projector

B.         Street lighting

C.         Photography

D.         None of the above

41. Which of the following will need highest level of illumination?

A.         Hospital wards

B.         Proofreading

C.         Bedrooms

D.         Railway platforms

42. Illumination of one lumen per sq. meter is called _______.

A.         Foot candle

B.         Candela

C.         Lux

D.         Lumen meter

43. Which photometer depends on its operation on Lambert’s cosine law?

A.         Trotter Illumination Photometer

B.         Guild’s Flicker Photometer

C.         LummerBrodhum Photometer

D.         Macbeth lllumino meter

44. which of the following is not the standard rating of GLS lamps?

A.         15 W.

B.         40 W.

C.         75 W.

D.         100 W.

45. Due to moonlight, illumination is nearly _______.

A.         0.3 lumen/m²

B.         30 lumen/m²

C.         300 lumen/m²

D.         3000 lumen/m²

46. The level of illumination on surface least relies upon _______.

A.         Type of reflector used

B.         Distance of the source

C.         Ambient temperature

D.         Candle power of the source

47. One lux is the same as _______.

A.         one lumen/sq. m

B.         one lumen/sq. cm

C.         one lumen/100 sq. m

D.         one lumen/1000 sq. m

48. The color temperature of day light is around ______.

A.         50 K

B.         160 K

C.         600 K

D.         6000 K

49. Which filament material has the lowest melting point?

A.         Tantalum

B.         Osmium

C.         Carbon

D.         Tungsten

50. Which of the following material is used as filament in the incandescent lamps?

A.         Tungsten

B.         Silver

C.         Osmium

D.         Tantalum

51. Lumen/watt is the unit of

A.         Light flux

B.         Luminous intensity

C.         Luminous efficiency

D.         Brightness

52. The melting point of Tungsten is about ______.

A.         2400°C

B.         2600°C

C.         2800°C

D.         3400°C

53. Filament lamps normally operate at a power factor of _______.

A.         Unity

B.         0.5 Lagging

C.         0.8 Lagging

D.         0.85 Leading

54. _______ will need lowest level of illumination.

A.         Displays

B.         Railway platform

C.         Fine engravings

D.         Auditoriums

55. In house the illumination is in the range of _______.

A.         60 – 65 lumens/watt

B.         35 – 45 lumens/watt

C.         10 – 20 lumens/watt

D.         2 – 5 lumens/watt

56. The unit of luminous flux is ______.

A.         Watt/m²

B.         Watt

C.         Lumen/m²

D.         Lumen

57. Which of the following statements is correct?

A.         Light consists of shooting particles

B.         Light consists of electromagnetic waves

C.         Light is a form of electrical energy

D.         Light is a form of heat energy

58. Which photometer depends on its operation on Lambert’s cosine law?

A.         Guild’s Flicker Photometer

B.         Macbeth lllumino meter

C.         Trotter Illumination Photometer

D.         LummerBrodhum Photometer

59. In case of ______ least illumination level is required

A.         Hospital wards

B.         Skilled bench work

C.         Drawing offices

D.         Fine machine work

60. Standard wattage of 3 ft. fluorescent tube is _______.

A.         20 W

B.         40 W

C.         60 W

D.         80 W

61. For the same wastage which lamp is cheapest?

A.         GLS lamps

B.         Fluorescent tube

C.         Sodium vapor lamp

D.         Mercury vapor lamp

62. The output of a tungsten filament lamp depends on _______.

A.         Size of shell

B.         Size of lamp

C.         Temperature of filament

D.         None of above

63. The rate of evaporation of tungsten filament in a lamp depends on _______.

A.         Glass shell diameter

B.         Vapor pressure inside

C.         Exhaust tube diameter

D.         None of above

64. Carbon arc lamps are commonly used in _______.

A.         Street lighting

B.         Photography

C.         Domestic lighting

D.         Cinema Projectors