luminous intensity वाक्य

A source with a luminous intensity of I = 1 candela at a distance of r = 50 km ( converting to SI units for sanity's sake ) produces an illuminance of E = I / r 2 = 4 * 10-10 lux ( or lumen / m 2 ).
Luminous intensity is analogous to radiant intensity, but instead of simply adding up the contributions of every wavelength of light in the source's spectrum, the contribution of each wavelength is weighted by the standard luminosity function ( a model of the sensitivity of the human eye to different wavelengths ).