A small, monochromatic light source, radiating at 500 nm, is rated at 500 W.
(a) If the source radiates uniformly in all directions, determine its radiant intensity.
(b) If the surface area of the source is 5 cm², determine the radiant excitance.
(c) What is the irradiance on a screen situated 2 mm from the source, with its surface normal to the radiant flux?
(d) If the receiving screen contains a hole with diameter 5 cm, how much radiant flux gets through?
