Solving a problem in physics section 1 point 70 optics

Solving a problem in physics section 1 point 70 optics

70. At the bottom of a vessel filled with water (n = 1,33) to a height h = 25 cm, is a point light source. It floats at the water surface an opaque plate so that the center plate is placed over a light source. Determine the minimum diameter of the plate, in which light passes through the water surface.

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