CLD Photometry & Light Measurement

Question 1

What unit is used to measure luminous flux?

Accepted Answer

Lumen

Answer

Candela

Answer

Lux

Answer

Watt

Question 2

Which unit measures illuminance, the amount of light falling on a surface?

Accepted Answer

Lux

Answer

Candela per square meter

Answer

Lumen

Answer

Watt per square meter

Question 3

A goniophotometer is primarily used to measure:

Accepted Answer

Luminous intensity distribution of a luminaire

Answer

Color rendering index of a lamp

Answer

Total luminous flux using an integrating sphere

Answer

Correlated color temperature

Question 4

According to the inverse square law, if the distance from a point source doubles, the illuminance on a surface:

Accepted Answer

Decreases to one-quarter

Answer

Doubles

Answer

Remains the same

Answer

Decreases by half

Question 5

Luminous intensity is measured in which unit?

Accepted Answer

Candela

Answer

Lumen

Answer

Lux

Answer

Nit

Question 6

What is the SI unit for luminance?

Accepted Answer

Candela per square meter (cd/m²)

Answer

Lux

Answer

Lumen per steradian

Answer

Footlambert

Question 7

The Color Rendering Index (CRI) is measured on a scale from 0 to:

Accepted Answer

100

Answer

50

Answer

200

Answer

1000