(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

a soap film of refractive index 1.333 is illuminated with white light at an angle of 45.the light refracted by it is examined and two bright bands are focussed corresponding to wavelengths 6.1 X 10 to the power -5 and 6.0 X 10 to the power -5.find thickness "t" of the film

2. Relevant equations

since it is given as destructive interference,formula will be

2 Xrefractive index(myu) X t Xcosr=n Xlamda

3. The attempt at a solution

2 X 1.333 X t X cos45=?

what is the wavelength i should take.there are two.its bit confusing for me......please help me.........

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# Homework Help: An interference problem

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