A source emits light of wavelengths 555 nm and 600 nm . The radiant flux of the 555 nm part is 40 W while that of the 600 nm part is 30 W . The relative luminosity at 600 nm is 0.6 . Determine the total luminous flux.

Step-by-step solution

The total luminous flux is the sum of the luminous fluxes for each wavelength. The luminous flux for a given wavelength is calculated as _v = 685 V( ) _e( ) , where V( ) is the relative luminosity and _e( ) is the radiant flux. At 555 nm , the relative luminosity is maximum, so V(555 nm ) = 1 . Luminous flux for the 555 nm part: _ v1 = 685 1 40 = 27400 lumen For the 600 nm part, the relative luminosity is given as V(600 nm ) = 0.6 . Luminous flux for the 600 nm part: _ v2 = 685 0.6 30 = 12330 lumen Total luminous f