Solving a problem in physics section 76 point 67 optics

Solving a problem in physics section 76 point 67 optics

67. Using a diffraction grating with a period of d = 20 mm, it is required to resolve a sodium doublet with sodium lengths with wavelengths λ1 = 589.0 nm and λ2 = 589.6 nm in the second-order spectrum. Determine at what minimum length in the lattice this is possible.

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Detailed solution. Decorated in Microsoft Word 2003. (Target decided to use formula editor)