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Thin-Film Interference

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We have not covered in class yet and the book does not offer much help. Is it asking for the value (m)? If so how is that determined? Thanks.

Light of wavelength 616 nm (in vacuum) is incident perpendicularly on a soap film (assume n = 1.36) suspended in the air. What are the two smallest nonzero film thicknesses (in nm) for which the reflected light undergoes constructive interference?

(a) ___nm (smallest thickness)

(b) ___nm (next smallest thickness)

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Dear student,

This is a standard physics problem. Sometime they ask about reflected light, sometimes transmitted light. ...

Solution Summary

This solution contains an annotated diagram and step-by-step explanations of wave concepts to determine the nonzero film thickness for which reflected light undergoes constructive interference.

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Thin film interference and air gap of variable thickness

** Please see the attached file for the complete problem description **
Say you saw the following interference pattern due to air between two glass slides:
(please see the attached file)

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