In order to change the color of light you must change

a. only the frequency of the light
b. only the wavelength of the light
c. either the frequency or the wavelength of the light
d. neither the frequency nor the wavelength of the light

What is the thinnest soap film (excluding the case of zero thickness) that appears black when illuminated with light with a wavelength of 480 ? the index of refraction of the film is 1.34, and there is air on both sides of the film. express your answer in nanometers. hint 1. how to approach th