A thin layer of oil (n=1.50) floats on water. Destructive interference is observed for reflected light of wavelengths 480 nm and 600 nm, each at different location.
(a) If the order number is the same for both wavelengths, which wavelength is at the greater thickness: (1) 480 nm, or (2) 600 nm? Explain.
(b) Write the general condition of destructive interference for reflected light.
(c) Find the two minimum thickness of the oil film, assuming normal incidence.