A single photon cannot be produced by annihilation of a particle pair at rest because:

  1. mass would increase
  2. energy would not be conserved
  3. charge would not be conserved
  4. momentum would not be conserved
Answer

D) momentum would not be conserved

Total momentum is zero. SLO P-11-F-28 · Understanding

Physics MCQ · More Nuclear and Particle Physics MCQs · Practise