Задача 40884.

On a thin soap film (n = 1,3) 1,25 mm thick is normally incident monochromatic light. The reflection film seems light. What is the minimum thickness necessary to take a thin film of turpentine (n = 1,48), that it is in the same conditions, appeared dark?

Detailed solution with a short recording conditions, laws and formulas used in the decision, the withdrawal of the calculation formula and the answer.
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