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Homework Help: Calculate the average binding energy per nucleon

  1. May 20, 2008 #1
    a) Calculate the average binding energy per nucleon in the deuterium nucleus.
    b) The energy that binds an orbiting electron to the hydrogen nucleus is 13.4 eV. Calculate the ratio of the binding energy per nucleon to the binding per electron in deuterium. Which particle is held more tightly, the electron or the neutron?

    I already worked out the average binding energy per nucleon as 1.112 MeV/c^2 in the last question.

    1 eV = 1.0*10^6 MeV/C^2, so wouldn't that make the binding energy of an electron much stronger than that of a neutron?
  2. jcsd
  3. May 20, 2008 #2
    Be careful, ask yourself - does that seem reasonable?
    That is not an energy, it is a mass.
  4. May 20, 2008 #3


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    Staff Emeritus
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    Careful, what you have actually calculated there is the mass deficit per nucleon, notice the factor of c-2.
    You need to be careful with your units here, an extra factor of c-2 has just popped up from nowhere. Again, you have quoted units of mass. You also need be careful when converting from eV to MeV.

    1eV = 1x10-6MeV
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