﻿ A 1-MeV positron collides head-on with a 1-MeV electron and they are annihilated, producing -rays. Compute total energy of the resulting -rays and their wavelength.Given : rest mass of electron or positron = 0.000549 u, .  : Kaysons Education

# A 1-MeV Positron Collides Head-on With A 1-MeV Electron And They Are Annihilated, Producing -rays. Compute Total Energy Of The Resulting -rays And Their Wavelength.Given : rest Mass Of Electron Or Positron = 0.000549 U, .

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## Question

### Solution

Correct option is

The annihilation equation is

(positron)           (electron)

The total energy of the -rays produced is equal to the sum of the rest-mass energies of the positron and the electron, plus their initial kinetic energies. Thus

The energy is shared by the two -photon is

The wavelength of the -photon is

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