試題詳解

20. When a photon undergoes Compton scattering with an electron and is scattered at a 90° angle relative to its original direction, its energy after scattering is half of its original energy. What is the initial wavelength of the photon?
(A) 1.33 nm
(B) 2.43 nm
(C) 1.33 pm
(D) 2.43 pm
(E) None of the above