(3-15)   When an electron (mass = 9.11 x 10-31 kg)  meets a positron (an anti-electron; same mass as an electron) they annihilate one another, producing two photons of gamma-radiation. The wavelength of the photons is 2.42 x 10-12 m. 

Assuming the kinetic energy of the two particles was negligible when they met, see if these data support Einstein’s equation. '

(Speed of light, c = 3.00 x 108 ms-1; Planck’s constant, h = 6.626 x 10-34 Js).