Question

If a 72-candela light source is located at a distance of 3 meters from a surface, the illuminance on the surface is

A. 216 lux.

  B. 8 lux.   C. 24 lux.   D. 648 lux

Answer 1

If a 72-candela light source is located at a distance of 3 meters from a surface, the illuminance on the surface is _____.

The formula of illuminance is equal to:
Illuminance = distance * light
Illuminance = 3 * 72
Illuminance = 216 lux.

So the correct answer is letter (A) 216 lux.