A photon with an energy of 0.51 MeV was scattered by a

A photon with an energy of 0.51 MeV was scattered by a free electron and lost half of its energy. Determine the magnitude of the photon scattering angle.
Problem 50123. A detailed solution with a brief note of the conditions, formulas and laws used in the solution, the derivation of the calculation formula and the answer.
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