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Homework Help: Energy decay

  1. Nov 15, 2008 #1
    1. The problem statement, all variables and given/known data
    Radium-226 decays with a half-life of 1.60E3 years via the process:
    Ra -> Rn + He + Energy

    (Masses : Ra = 226.025403u, Rn = 222.017570u, He - 4.002603u)

    How much energy, in MeV, is released in each decay?

    2. Relevant equations
    E= mc^2


    3. The attempt at a solution
    E of Ra - E of Rn - E of He = Energy released
    Energy = mc^2 - mc^2 -mc^2
    E = (226.025403)(3E+8)-(222.017570)(3E+8)-(4.002603)(3E+8)= 1568700J = 9.79E+24 = 9.79E+18 MeV ????
     
  2. jcsd
  3. Nov 17, 2008 #2

    malawi_glenn

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    Science Advisor
    Homework Helper

    no, how many MeV is one u?
     
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