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Homework Help: Modern physics question

  1. Feb 3, 2005 #1
    The free neutron is known to decay into a proton, an electron, and an antineutrino v' (of negligible rest mass) according to n-->p+e+v'. The decay products are measured to have a total kinetic energy of 0.781+/-0.005 MeV. Show that this observation is consistent with the excess energy predicted by Einstein's mass-energy relationship.

    Doing this problem I get: (Mn-Mp-Me)c^2=(940 MeV/c^2-938 MeV/c^2-0.511 MeV/c^2)c^2=1.489 MeV which is not equal to the change in kinetic energy 0.781+/-0.005 MeV
  2. jcsd
  3. Feb 3, 2005 #2
    I get .785 MeV. Try using more accurate numbers. See eg: http://www.mcelwee.net/html/table_of_physical_constants.html [Broken]
    Last edited by a moderator: May 1, 2017
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