47. The light normally incident alternately on the two plates, made of the same substance, having respective thicknesses x1 = 5 mm, x2 = 10 mm. Determine the absorption coefficient of the substance, if the intensity of the transmitted light through the first plate is 82%, and in the second - 67% of the initial intensity.

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