Solving a problem in physics section 13 point 62 optics

Solving a problem in physics section 13 point 62 optics

62. For measuring the refractive index of ammonia in one arm of a Michelson interferometer placed evacuated tube length l = 14 cm. The ends of the tube closed plane-parallel panes. When filling the tube with ammonia interference pattern for the wavelength λ = 590 nm shifted to k = 180 bands. Find the index of refraction n ammonia.

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