A thin film of oil strongly reflects blue light. Should the oil be made thicker or thinner to reflect red light?

Answer 1

Which is the shorter wavelength ?

Answer 2

the blue light is the shorter wavelength. What does that mean in regards to this?

Answer 3

Think about it or google oil slick reflection wavelengths and look at the geometry in the images. You will see that the shorter the wavelength the thinner the film.

Answer 4

Thank you!