# Question

What is the threshold energy for the production of an electron–positron pair?

## Answer to relevant Questions

What is the energy of the photons produced in proton–antiproton pair annihilation, assuming that both particles are essentially at rest initially? Abeam of electrons moving at 5.0 x 105 m/s is incident on a single slit that is wide. On a screen that is 1.0 m behind the slits, an electron diffraction pattern is observed. What is the width of the central maximum? Electrons are accelerated from rest through an electric potential difference. (a) If this potential difference increases to four times the original value, the new de Broglie wavelength will be (1) four times, (2) twice, (3) ...Nuclide A has a half-life that is one-third that of nuclide B. The type A sample starts with twice the number of undecayed nuclei as in the sample of type B. Compare the initial sample activities expressed as a ratio of the ...Theoretically, the tumor- killing efficiency of particle beams is much greater than that of a beam of X- rays or gamma rays. Explain why this is true.Post your question

0