My lecturer has given me this formula for reflective diffraction(adsbygoogle = window.adsbygoogle || []).push({});

m landa = d (cos a - cos b)

where

m is order #

landa is wavelength

d is slit seperation

a is angle of inicdence

b is angle of reflection

The problem I have is I wasn't given any justification of this and have no idea where it comes from

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# Reflection Diffraction Gratings

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