Solving a problem in physics section 2 point 41 optics

Solving a problem in physics section 2 point 41 optics

41. Installation for observation of Newton´s rings is illuminated by monochromatic light incident normally. When filling the space between the lens and a glass plate with a transparent liquid radii dark rings in reflected light in the 1.21-fold decreased. To determine the refractive index n2 of the liquid.

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