posted by Anthony .
5. The surface of a glass plate (index of refraction n3 = 1.50) is coated with a transparent thin film (index of refraction n2 = 1.25). A beam of monochromatic light of wavelength 6.0 X 10^-7 meter traveling in air (index of refraction n1 = 1.00) is incident normally on surface S1 as shown above. The beam is partially transmitted and partially reflected.
(a) Calculate the frequency of the light.
(b) Calculate the wavelength of the light in the thin film.
The beam of light in the film is then partially reflected and partially transmitted at surface S2·
(c) Calculate the minimum thickness d1 of the film such that the resultant intensity of the light reflected back into the air is a minimum.
(d) Calculate the minimum nonzero thickness d2 of the film such that the resultant intensity of the light reflected back into the air Is a maximum.
I need help on this plzzz