What happens to the wavelength of an X-ray photon when it undergoes inelastic scattering off a loosely bound electron, a phenomenon known as the Compton effect?

💡 Solution & Explanation

The Compton effect demonstrates that when an X-ray photon collides inelastically with a loosely bound electron, it transfers a portion of its energy to the recoil electron, resulting in a decreased frequency and increased wavelength for the scattered photon. This quantum mechanical phenomenon provides irrefutable evidence of the particle nature of electromagnetic radiation, as predicted by the conservation of momentum and energy. Arthur Compton received the Nobel Prize in Physics in 1927 for this discovery.