Answer:
The surface from the source is 5 m.
Explanation:
Given that,
Light intensity = 100 candelas
Illuminance = 4 lux
The formula of illumination is
According to illumination law,
The intensity of illuminance of the the light source is inversely proportional to the square of the distance from the source.
The formula of illumination is
[tex]E\propto\dfrac{1}{d^2}[/tex]
[tex]E=\dfrac{I}{d^2}[/tex]
Where, E = illuminance
I = luminous Intensity of the light
D = distance
We substitute the value into formula
[tex]d^2=\dfrac{I}{E}[/tex]
[tex]d^2=\dfrac{100}{4}[/tex]
[tex]d^2=25[/tex]
[tex]d = 5\ m[/tex]
Hence, The surface from the source is 5 m.
