As a soap bubble thins it becomes dark, because thepath length difference becomes small compared with thewavelength of light and there is a phase shift at the topsurface. If it becomes dark when the path length difference isless than one-fourth the wavelength, what is the thickest thebubble can be and appear dark at all visible wavelengths?Assume the same index of refraction as water. (b) Discussthe fragility of the film considering the thickness found

As a soap bubble thins it becomes dark, because thepath length difference becomes small compared with thewavelength of light and there is a phase shift at the topsurface. If it becomes dark when the path length difference isless than one-fourth the wavelength, what is the thickest thebubble can be and appear dark at all visible wavelengths?Assume the same index of refraction as water. (b) Discussthe fragility of the film considering the thickness found

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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Similar questions

An inventor notices that a soap bubble is dark at its thinnest and realizes that destructive interference is taking place for all wavelengths. How could she use this knowledge to make a nonreflective coating for lenses that is effective at all wavelengths? That is, what limits would there be on the index of refraction and thickness of the coating? How might this be impractical?
A transparent film of thickness 250 nm and index of refraction of 1.40 is surrounded by air. What wavelength in a beam of white light at near-normal incidence to the film undergoes destructive interference when reflected?
Check Your Understanding In the system used in the preceding examples, at what angles are the first and the second bright fringes formed?
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A film of oil on water will appear dark when it is very thin, because the path length difference becomes small compared with the wavelength of light and there is a phase shift at the top surface. If it becomes dark when the path length difference is less than one-fourth the wavelength, what is the thickest the oil can be and appear dark at all visible wavelengths? Oil has an index of refraction of 1.40.