Find the mean illuminance of the irradiated part of an opaque sphere receiving
Channel: Doubtnut
Date: 16/08/2020

Find the mean illuminance of the irradiated part of an opaque sphere receiving  (a) a parallel luminous flux resulting in illuminance `E_(0)` at the point of normal incidence,  (b) light from a point isotropic source located at a distance `l = 100 cm` from the cnetre of the sphere, the radius of the sphere is `R = 60 cm` and the luminous intensity is `I = 36 cd`.