- #1
m00nd0g68
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A neutron at rest in the laboratory spontaneously decays into a proton, an electron, and a small essentially massless particle called a neutrino. Calculate the kinetic energy of the proton and the electron in each of the following cases:
a) the neutrino has no kinetic energy
b) the neutrino has 300keV of kinetic energy and is traveling opposite the proton and the same direction as the electron
c) the neutrino has 300keV of kinetic energy and is traveling perpendicular to the proton and electron, which are traveling opposite of each other.
I have solved part a. But part b I am having a problem with. I understand that the neutrino’s E = K + E0 = K + mc2 = K = 300keV (where mc2 = 0 because it has no mass) but I don’t know how to use this with the energies of the other two. Do I simply subtract the energies of the proton, electron and the given K of the neutrino to get an amount that is a new total energy? On part c how do I handle the 300keV of the neutrino that is traveling perpendicularly to the proton and electron?
Any hints would be appreciated…
moondog
a) the neutrino has no kinetic energy
b) the neutrino has 300keV of kinetic energy and is traveling opposite the proton and the same direction as the electron
c) the neutrino has 300keV of kinetic energy and is traveling perpendicular to the proton and electron, which are traveling opposite of each other.
I have solved part a. But part b I am having a problem with. I understand that the neutrino’s E = K + E0 = K + mc2 = K = 300keV (where mc2 = 0 because it has no mass) but I don’t know how to use this with the energies of the other two. Do I simply subtract the energies of the proton, electron and the given K of the neutrino to get an amount that is a new total energy? On part c how do I handle the 300keV of the neutrino that is traveling perpendicularly to the proton and electron?
Any hints would be appreciated…
moondog