Question

An electron positron pair is produced by a gamma ray photon of energy 2.26 MeV. How much kinetic energy (expressed in MeV) is imparted to each of the two charged particles of the pair produced?

• A. 1.24
• B. 0.62
• C. 1.13
• D. 1.62

Answer 1

The correct option is B

0.62

The energy equivalent of the mass of electron is 0.51 and similarly the energy equivalent of the mass of positron is 0.51 . Thus a total of 1.02 energy is used for the creation of mass of the particles in the pair. The remaining energy 1.24 is shared equally by the two particles as kinetic energy. }