# Calculating the Energy of a Neutrion

1. Sep 12, 2008

### edziura

The energy of a proton can be calculated using Einstein's relativistic energy equation (kinetic + rest energy). The energy of a photon can be calculated using E = h nu.

Is there a "formula" for calculating the energy of a neutrino?

2. Sep 12, 2008

### malawi_glenn

yes, the neutrino has as we know now mass, so energy of a neutrino is kinetic + rest energy.

3. Sep 12, 2008

### Staff: Mentor

The energy of a proton can also be calculated using $E = h \nu$ if we know the frequency $\nu$ of its wavefunction $\Psi$. The energy of a photon can also be thought of as kinetic plus rest energy, with the rest energy being zero.

You can calculate the energy of a neutrino either way, just as with the other two particles. As malawi_glenn noted, neutrinos do have a (small) mass, so they also have a (small) rest energy.