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Homework Help: The energy released for white dwarf collapsing into neutron star

  1. Jun 8, 2014 #1
    The question is attached.
    I'm not sure how to approach to part (b).
    The energy released could be in 3 forms, the rest mass energy for those matter ejected during supernova explosion, the binding energy released as the atomic structure changed, the ejected matter carries off some kinetic energy.

    I assume the question is only asking for the binding energy (as it mentioned "photons" in part (e))?
    Quantum density, the degenerated pressure from electrons and neutrons are mentioned during lecture, but I'm not sure if these are necessary for this question

    Please share some ideas with me, or maybe some solutions. Thank you

    Attached Files:

  2. jcsd
  3. Jun 9, 2014 #2

    Simon Bridge

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    Does the collapse of a white dwarf to a neutron star generally result in a supernova?
    Notice that part (c) asks to compare with the energy released from a supernova ... should be a clue.

    What are you told changes in the collapse?
    What kind of energy do you normally associate with this change?

    You'll need to check your notes about "quantum density" to see if you need to consider it explicitly.
  4. Jun 10, 2014 #3
    Hint: Use the virial theorem (2T + V = 0). How much does the total energy change, compared to the potential energy? What happens to the change in energy?
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