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

A laser with wavelength d/8 is shining light on a double slit with slit separation 0.300 . This results in an interference pattern on a screen a distance L away from the slits. We wish to shine a second laser, with a different wavelength, through the same slits.

What is the wavelength λ_{2}of the second laser that would place its second maximum at the same location as the fourth minimum of the first laser, if d= 0.300 ?

2. Relevant equations

dsinθ=mλ

dsinθ=(m+1/2)λ

λ_{1}=d/8 <---- not sure about this one but problem statement suggests it.

d=3*10^{-4}m

3. The attempt at a solution

sinθ=((m+1/2)λ_{1})/d where m=-4

sinθ=((m+1/2)λ_{2})/d where m= 2

set equal and i got -0.0525mm.

im not sure where I'm misunderstanding but it could be my understanding of m values, reading the problem wrong or simply a misunderstanding of the whole question posed. Any takers?

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# Homework Help: Two source interference determining wavelength

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