In one section of the pool, there is a thin film of oil on the surface of the water. The thickness of the film is

Question

1.0 X l0^-7 meter and the index of refraction of the oil is 1.5. The light source is now held in the air and illuminates the film at normal incidence, as shown above.
d. At which of the interfaces (air oil and oil water), if either, does the light undergo a 180° phase change upon reflection?
e. For what wavelengths in the visible spectrum will the intensity be a maximum in the reflected beam?

Answer 1

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