In a dark indoor environment one single Axis illuminator is available. At a distance of 1 m (3 ft 3 in) away from the illuminator the light intensity is 1024 lux. At what distance from the light source will the light intensity be 256 lux?
A) 2 m (6 ft 7 in)
B) 4m{13 ft 1 in)
C) 8 m (26 ft 3 in)
D) 16 m (52 ft 6 in)

Question

Quizplus · Accepted Answer

The intensity of light decreases with the square of the distance from the source. If the intensity is 1024 lux at 1 m, it will be 256 lux at 2 m, since (1/2)^2 = 1/4, and 1024/4 = 256.

In a Dark Indoor Environment One Single Axis Illuminator Is