A film of oil on water will appear dark when it is very thin,because the path length difference becomes small comparedwith the wavelength of light and there is a phase shift at thetop surface. If it becomes dark when the path lengthdifference is less than one-fourth the wavelength, what is thethickest the oil can be and appear dark at all visiblewavelengths? Oil has an index of refraction of 1.40.

A film of oil on water will appear dark when it is very thin,because the path length difference becomes small comparedwith the wavelength of light and there is a phase shift at thetop surface. If it becomes dark when the path lengthdifference is less than one-fourth the wavelength, what is thethickest the oil can be and appear dark at all visiblewavelengths? Oil has an index of refraction of 1.40.

University Physics Volume 3

17th Edition

ISBN:9781938168185

Author:William Moebs, Jeff Sanny

Publisher:William Moebs, Jeff Sanny

Chapter3: Interference

Section: Chapter Questions

Problem 91CP: A film of oil on water will appear dark when it is very thin, because the path length difference...

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