Problem states: Wavelengths of 690 and 575nm are observed when white light is directed on a film floating in water. The index of the film is 1.25, and the index of water is 1.33.(adsbygoogle = window.adsbygoogle || []).push({});

What is the thichkness?

I know the phase is shifted by pi., but other than that I am not sure where to go with this problem!

Can I get a nudge in the right direction???

Thanks

--k

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# Homework Help: Thin-film problem

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