(Determination of photon wavelength from rest-frame annihilation) An electron and a…

PHYSICS · Subjective · A Level · Physics · Particles and radiation · Particles and radiation

Problem

(Determination of photon wavelength from rest-frame annihilation) An electron and a positron, each initially at rest in vacuum, annihilate to produce two photons of equal energy moving in opposite directions. Given: Rest mass of electron me=9.11×10−31 kgm_{e}=9.11\times10^{-31}\,\text{kg} Planck constant h=6.63×10−34 J sh=6.63\times10^{-34}\,\text{J s} Speed of light c=3.00×108 m s−1c=3.00\times10^{8}\,\text{m s}^{-1} (a) Calculate the energy of one of the photons produced. (b) Hence determine the wavelength of each photon. (c) Express this wavelength in nanometres.

Related theory

Browse the problem library