What is the amount of energy given off when an electron and a positron anhilalate?
Asked by: Bill Devenport
Answer
Using 9 x 10-31 Kg. as the mass of each particle, and knowing that their combined mass
will be totally converted to energy, you can use Einstein's famous E = mc2 (where c = the
speed of light in vacuum = 3 x 108 m/sec) to determine the total energy output of the electron/positron annihilation:
E = (mass of electron + mass of positron) x (speed of light in m/sec)2
E = 2 x (9 x 10-31)kg x (9 x 1016)m2/sec2
E = 1.6 x 10-13 kg m2/sec2 = 1.6 x 10-13 Joules
Answered by: Paul Walorski, B.A. Physics, Part-time Physics Instructor
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