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Physics questions help?
Under certain conditions an electron and a positron can annihilate each other and produce two photons, Annihilation is a process in which a particle and its antiparticle are converted into energy.
1. Determine the combined energy in joules of the photons created when an electron and a positron annihilate each other.
2. Assuming the photons are identical, express the energy of one photon in electron volts.
1 Answer
- Anonymous1 decade agoFavorite Answer
E = m c^2 = 2 . 9.11 . 10^–31 . 9 . 10^16 = 1.64 . 10^–13 J
2. energy of one photon = 0.82 .10^–13 J = 8.2 . 10^–14 / 1.6 . 10^–19 = 5.12 . 10^5 eV
512 keV ( a famous number - keeps coming up. )
Source(s): Old teacher