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Binding Energy question

  1. Jan 22, 2009 #1
    The mass of the hydrogen atom is smaller than the sum of the masses of a proton and an electron. The mass difference is converted into binding energy. Mass was converted, and you know where it went (into binding energy). Where did the mass come from, the electron or proton??
  2. jcsd
  3. Jan 22, 2009 #2


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    Mass was not converted into energy.
    The mass of a hydrogen atom is M_hyd=M_p +m_e +U_binding,
    with U_binding=-13.6 eV.
  4. Jan 22, 2009 #3
    did the binding energy come from the proton or the electron, is what i'm asking.
  5. Jan 23, 2009 #4

    Vanadium 50

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    What clem is saying is "neither". There are three terms in his expression, and it comes from the third term.
  6. Jan 23, 2009 #5


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    The binding energy comes from the interaction of both the electron and the proton. Togehter they'll draw eachother down into a potential, and since Energy = mass, the total system will have mass less than mass of lone constituents.
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