Fusion

Questions:

  1. What nuclei are fused in the nuclear reaction of a hydrogen bomb?
  2. Calculate the energy release (in MeV) in the D-T fusion reaction?
  3. What function does styrofoam perform in a hydrogen bomb?
  4. Why is a fission bomb needed as part of an H-bomb?

Answers:

  1. What nuclei are fused in the nuclear reaction of a hydrogen bomb?

    H2 + H3 → He4 + n + 17.5 MeV
    where H2 is deuterium and H3 is tritium.

  2. Calculate the energy release (in MeV) in the D-T fusion reaction?

    Energy = (Massbefore- Massafter) c2 (See answer to problem 1).
    E = {(3.3454 × 10-27 kg + 5.0097 × 10-27 kg) - (6.06483 × 10-27 kg + 1.6754 × 10-27 kg)} x (3.0 × 108 m/s)2
    E = 2.8 × 10-12 joules = 17.5 MeV
    where 1 joule = 6.25 × 1012 MeV

  3. What function does styrofoam perform in a hydrogen bomb?

    Styrofoam absorbs gamma rays and is compressed. Because the styrofoam surrounds the reactants, they is compressed to the density needed to sustain fusion.

  4. Why is a fission bomb needed as part of an H-bomb?

    In order for the hydrogen bomb to work, the LiD must be compressed (via the gamma radiation emitted from the primary) and then bombarded by neutrons (also from the primary) to create the needed tritium. The primary also provides the proper conditions, a highly elevated temperature and pressure, so that fusion can occur.