ILLUMINATION QUIZ

The work of ballast in a fluorescent tube is to

provide a kick start when voltage is induced.

None of these.

limit the flow of current.

both ‘a’ and ‘b’.

TRUE ANSWER : ?
YOUR ANSWER : ?

Which lamp has the best Colour Rendering Index (CRI)?

High pressure sodium vapour

LED

Fluorescent

Incandescent

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?

4

2

6

5

TRUE ANSWER : ?
YOUR ANSWER : ?

Candela/metre square is the unit of which photometric quantity?

Illuminance

Luminous Intensity

Luminance

Luminous flux

TRUE ANSWER : ?
YOUR ANSWER : ?

Unit of luminous flux is

candela.

lux.

lumens.

steradians.

TRUE ANSWER : ?
YOUR ANSWER : ?

Luminous efficiency of a fluorescence lamp is

40 lumens / watt.

70 lumens / watt.

60 lumens / watt.

30 lumens / watt.

TRUE ANSWER : ?
YOUR ANSWER : ?

Which lamp has a negative Colour Rendering Index (CRI)?

LED

Fluorescent

High pressure sodium vapour

Low pressure sodium vapour

TRUE ANSWER : ?
YOUR ANSWER : ?

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

To convert AC to DC

To convert DC to AC

None of these

Both ‘a’ and ‘b’

TRUE ANSWER : ?
YOUR ANSWER : ?

Solid angle is expressed in terms of

steredians.

radians / meter.

degree.

radians.

TRUE ANSWER : ?
YOUR ANSWER : ?

A 200 candle power lamp is hung 4 m above the centre of circular area of 5 m diameter. The illumination at centre of the area is

13.5 lux.

12.5 lux.

18.5 lux.

17.5 lux.

TRUE ANSWER : ?
YOUR ANSWER : ?

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