Physics-
General
Easy
Question
A gamma ray photon creates an electron- positron pair. If the rest mass energy of an electron is 0.5 MeV and the total K.E. of the electron- positron pair is 0.78 MeV, then the energy of the gamma ray photon must be
- 0.78 MeV
- 1.78 MeV
- 1.28 MeV
- 0.28 MeV
The correct answer is: 1.78 MeV
Energy of g-ray photon =
.
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