What is the maximum frequency photon of one of the photons produced when a electron and positron annihilate each other?

First we must remember that a positron is the antiparticle of the electron, meaning that they will both have the same amount of rest energy (0.510999 MeV) however since annihilation produces 2 gamma photons each photon will have the same rest energy as one of the particles (0.510999 MeV). We then use the equation E=hc/λ rearranged to λ=hc/E and then sub in:(6.63x10-34)(3x108)/(0.511x106)(1.60x10-19) Notice here that in the denominator i have converted (0.510999 MeV) into MeV and then multiplied by the charge of an electron to get the energy in Joules (J) .
This then gives us the maximum wavelength of a single photon during a photon-positron annihilation: 2.43x10-12m

Related Physics A Level answers

All answers ▸

I have trouble visualizing simple harmonic motion, and remembering all the related equations. How should I think about it?


Show that the orbital period of a satellite is given by T^2=(4pi^2r^3)/(GM) where r is the orbital radius, G is the gravitational constant and M is the mass of the Earth. Then find the orbital radius of a geostationary satellite.


What is the photo-electric effect and what impact did it have on the development of Quantum Mechanics?


Describe and explain the motion of a skydiver from leaving the aircraft to reaching terminal velocity