Задача 50398.

A parallel beam of light normally falls on a diffraction grating with a period of d = 4 μm. The diffraction maxima of the second and fourth order are visible on the screen at angles of 20 ° and 30 °. Find the energy and momentum of the photons of the incident light.

Detailed solution with a brief record of the conditions, formulas and laws used in the decision, the conclusion of the calculation formula and the answer.
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