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Why do hydrogen and atom bombs have such force?

  1. Aug 21, 2010 #1
    Does it have to do with the strong nuclear force holding the atoms together being released?
     
  2. jcsd
  3. Aug 21, 2010 #2
    Why do hydrogen and atom bombs have such force? (re-post I)

    Does it have to do with the strong nuclear force holding the atoms together being released?

    This is a re-post I posted the original one in the wrong section, sorry. Please b detailed but now to detailed, I am only in 8th grade.
     
  4. Aug 21, 2010 #3

    mathman

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    The energy of these bombs comes from the mass to energy conversion resulting from fission (A bomb) or fusion (H bomb), from Einstein's famous formula E=mc2.
     
  5. Aug 21, 2010 #4
  6. Aug 21, 2010 #5

    mathman

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    Re: Why do hydrogen and atom bombs have such force? (re-post I)

    H-bombs (fusion) and A-bombs (fission) get their energy from mass to energy conversion, based on Einstein's formula E=mc2.
     
  7. Aug 21, 2010 #6

    Astronuc

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    Re: Why do hydrogen and atom bombs have such force? (re-post I)

    The energy is related to the nuclear force, which somewhat related to the strong force.

    http://en.wikipedia.org/wiki/Nuclear_force

    In fission, the excited U-236 nucleus (formed form the absorption of a neutron by a U-235 nucleus) or an excited Pu-240 nucleus (formed from the absorption of a neutron by a Pu-239 nucleus) fissions or splits into two new atoms, some free electrons and maybe some prompt gammas. The energy immediately released is about 180 MeV or so. More delayed energy is released in beta decay and gamma emission. The two new atoms move apart with about 165 MeV, with one having an energy of about 90-100 MeV and the other about 65-75 MeV. One (1) electron volt (eV) of kinetic energy is equivalent to 11605 K, so 1 MeV = 11.6 billion K and 100 MeV is about 1.16 trillion K. However, the fission products slam into other atoms and rapidly loose energy and that energy heats up the other solid atoms until the solid mass vaporizes at several 100 million K in several microseconds. It's that hot plasma and the beta, gamma and X-ray radiation that give off the tremendous heat and blast.

    Fusion occurs when lighter nuclei, usually isotopes of hydrogen (deuterium or tritium) fuse with each other, or other light nuclei like Li-6. The composite nucleus reconfigures and divides into a lower mass configuration with more tightly bound nuclei. The fusion products move apart with kinetic energies of 1 MeV or more, so the temperatures are on the order of a 100's of millions K.

    It is the binding energy that is release in the form of kinetic energy of the fission products or fusion products that causes the tremendous energy release for atomic or hydrogen bombs.

    The Strong Nuclear Force and Binding Energy
    http://theory.uwinnipeg.ca/mod_tech/node178.html

    http://phy.syr.edu/courses/PHY106.03Spring/Slides/PPT/Lec36-StrongForce.ppt [Broken]

    http://hyperphysics.phy-astr.gsu.edu/hbase/nucene/nucbin.html
    http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/radact.html
    http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/liqdrop.html
    http://hyperphysics.phy-astr.gsu.edu/hbase/nucene/fission.html
    http://hyperphysics.phy-astr.gsu.edu/hbase/nucene/fusion.html
     
    Last edited by a moderator: May 4, 2017
  8. Aug 21, 2010 #7

    vanesch

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    Although it is not wrong to say that the energy released by a nuclear reaction comes from the mass difference between initial and final state (the "mass defect") this is just as well the case with a chemical reaction, where the energy released of, say, petrol burning in a combustion engine ALSO "comes from the mass difference between the initial and final state".
    The only difference is that this chemical mass defect is much smaller than the nuclear mass defect, and this comes... because the nuclear binding energies are larger than the chemical binding energies. So we came to a full circle. In relativity, you can equate "released energy" and "mass defect", no matter the physical interaction that is responsible for the bond.

    So what's really the reason for that large amount of released energy ? Well, simply that the nucleus' binding energies are much larger, that is to say, the forces that keep together the protons and neutrons in a nucleus are much stronger than the forces that keep the electrons in the atoms and molecules.

    And why do people always bring up this "mass defect" ? Because the energy differences in nuclear reactions are so large that the mass defect becomes easily measurable, which is not the case for (most) chemical reactions.
     
  9. Sep 1, 2010 #8
    So much energy is released becouse:
    In an atom their is locked lots of joules of energy,but the heavier the atom the more energy but the harder to release it
    hydrogen is the simplest element so it is easyer to release it, so every atom has ltos of energy it is jsut that hydrogen is the simplest to unlock it.
     
  10. Sep 1, 2010 #9

    Danger

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    Sorry Nick, but that doesn't quite cut it. Hydrogen is certainly the simplest element, but in weapons applications a U-235 or Pu-239 fission bomb is use as the trigger for the subsequent inertial-confinement fusion reaction that makes it an H-bomb. Wrap a secondary jacket of U-238 around that, and you have a neutron bomb.
     
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