ILLUMINATION QUIZ

In illumination technology total lumens emitted by source / total lumens available after waste of light is equal to

absorption factor.

utilization factor.

waste light factor.

beam factor.

TRUE ANSWER : ?
YOUR ANSWER : ?

Total flux or lumens required in any lighting scheme depends inversely on

None of these

utilization factor.

reduction factor.

reflection factor.

TRUE ANSWER : ?
YOUR ANSWER : ?

What is the work of a driver in case of an LED?

To convert DC to AC

Both ‘a’ and ‘b’

None of these

To convert AC to DC

TRUE ANSWER : ?
YOUR ANSWER : ?

The illumination of the surface varies directly with cosine of the angle between normal to surface and direction of the inclined light is given by

Lambert’s cosine law.

None of these

both A and B.

law of square inverse.

TRUE ANSWER : ?
YOUR ANSWER : ?

Candela is the unit of which?

Frequency.

Wavelength.

Luminous flux.

Luminous intensity.

TRUE ANSWER : ?
YOUR ANSWER : ?

What will be the number of lamps, each having 300 lumens, required to obtain an average illuminance of 50 lux on a 4m × 3m rectangular room?

5

4

2

6

TRUE ANSWER : ?
YOUR ANSWER : ?

The illumination at a point 5 meters below a lamp in 6 lux. The candle power of the lamp is

140.

150.

200.

30

TRUE ANSWER : ?
YOUR ANSWER : ?

The work of ballast in a fluorescent tube is to

both ‘a’ and ‘b’.

limit the flow of current.

provide a kick start when voltage is induced.

None of these.

TRUE ANSWER : ?
YOUR ANSWER : ?

A 1000 W bulb fitted with a reflector illuminates an area of 3 m x 3 m with an average illumination of 450 lux. If the bulb has and efficiency of 9 lumens / watt the efficiency of the reflector is

45 %.

30 %.

70 %.

20 %.

TRUE ANSWER : ?
YOUR ANSWER : ?

Luminous efficiency of a fluorescence lamp is

70 lumens / watt.

30 lumens / watt.

60 lumens / watt.

40 lumens / watt.

TRUE ANSWER : ?
YOUR ANSWER : ?

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