Ray set forms a bright spot on the screen. When placed in its way a system of two polarizers, a spot on the screen disappeared. If, however, between the polarizers placed quartz plate, the intensity of light incident on the screen is equal to 12.5 percent of the original intensity. At what angle rotates the plane of polarization of light in the quartz plate?

Detailed solution shorthand terms, formulas, laws used in the decision, the withdrawal of the calculation formula and the response.
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