100 Important Illumination MCQ Question and Answer | PDF Free Download
1.Which of the following statements is correct?
- ALight is a form of heat energy
- BLight is a form of electrical energy
- CLight consists of shooting particles
- DLight consists of electromagnetic waves
2.Luminous efficiency of a fluorescent tube is
- A10 lumen/watt
- B20 lumen/watt
- C40 lumen/watt
- D60 lumen/watt
3.Candela is the unit of which of the following?
- AWavelength
- BLuminous intensity
- CLuminous flux
- DFrequency
4.Colour of light depends upon
- AFrequency
- BWave length
- CBoth (a) and (b)
- DSpeed of light
5.Illumination of one lumen per sq. meter is called ____________
- ALumen meter
- BLux
- CFoot candle
- DCandela
6.A solid angle is expressed in terms of ____________
- ARadians/metre
- BRadians
- CSteradians
- DDegrees
7.The unit of luminous flux is ___________
- AWatt/sq. Metre
- BLumen
- CLumen/sq. Metre
- DWatt
8.Incandescent lamps (Filament lamps) operate normally at a power factor of
- A0.5 lagging
- B0.8 lagging
- CUnity
- D0.8 leading
9.The filament of a GLS lamp is made of
- ATungsten
- BCopper
- CCarbon
- DAluminium
10.Fine diameter tungsten wires are made by
- ATurning
- BSwaging
- CCompressing
- DWire drawing
11.What percentage of the input energy is radiated by filament lamps?
- A2 to 5 percent
- B10 to 15 percent
- C25 to 30 percent
- D40 to 50 percent
12.Which of the following lamps is the cheapest for the same wattage?
- AFluorescent tube
- BMercury vapour lamp
- CGLS lamp
- DSodium vapour lamp
13.Which of the following is not the standard rating of GLS lamps?
- A100 W
- B75 W
- C40 W
- D15 W
14.In house the illumination is in the range of
- A2 ? 5 lumens/watt
- B10 ? 20 lumens/watt
- C35 ? 45 lumens/watt
- D60 ? 65 lumens/watt
15.?The illumination is directly proportional to the cosine of the angle made by the normal to the illuminated surface with the direction of the incident flux?. Above statement is associated with
- ALambert?s cosine law
- BPlanck?s law
- CBunsen?s law of the illumination
- DMacbeth?s law of illumination
16.The colour of sodium vapour discharge lamp is
- ARed
- BPink
- CYellow
- DBluish green
17.Carbon Arc lamps are commonly used in
- APhotography
- BCinema projectors
- CDomestic lighting
- DStreet lighting
18.Desired illumination level on the working plane depends upon
- AAge group observers and Whether the object is stationary or moving
- BSize of the object to be seen and its distance from the observer
- CWhether the object is to be seen for longer duration or shorter duration of time
- DAll above factors
19.On which of the following factors does the depreciation or maintenance factor depend?
- ALamp cleaning schedule
- BAgeing of the lamp
- CType of work carried out at the premises
- DAll of the above factors
20.In lighting installation using filament lamps 1% voltage drop results into
- ANo loss of light
- B1.5 percent loss in the light output
- C3.5 percent loss in the light output
- D15 percent loss in the light output