Gamma rays of wavelength pm from a radioactive source strike a block of aluminium and…
PHYSICS · Multi-part · Fermi University Physics · Quantum Mechanics · Origins of quantum theory · Origins of quantum theory
Quantum Mechanics: From the Photon to the Hydrogen Atom, Ch Light in lumps: blackbody radiation, the photoelectric effect and Compton scattering
Problem
Gamma rays of wavelength 5.00 pm from a radioactive source strike a block of aluminium and are Compton-scattered through 120∘ by the metal's loosely bound outer electrons, each electron effectively free and at rest before the collision. Take the Compton wavelength h/mec=2.43 pm and hc=1240 eV nm =1.240×106 eV pm.
((a)) Find the Compton shift λ′−λ and the scattered wavelength λ′, both in picometres.
((b)) Find the photon's energy before and after the collision, in keV.
((c)) Find the kinetic energy carried off by the recoiling electron, in keV.