The Physics
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Opus in profectus

Fission

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Problems

practice

  1. Write a fission bomb question that could be used in both the fission and nuclear weapons sections.
  2. Write something about a fission reactor.
  3. Write something — a fission weapon question that could be reused in the section on nuclear weapons if possible.
  4. A nucleus is a ball of positively charged protons glued together with the help of uncharged neutrons. Splitting a nucleus into two roughly equal halves increases the overall separation between the protons and reduces their electrostatic potential energy. Determine the fraction of the original electrostatic potential energy released in an idealized fission reaction.

statistical

  1. yield-to-weight.txt
    The efficiency of a nuclear weapon is often stated as a yield-to-weight ratio — the energy released after the weapon detonated divided by the mass of all its parts (nuclear fuel, conventional explosive, triggers, casing, etc.) before it detonated. The practical limit for all forms of nuclear weapon is thought to be 6 kt/kg (kilotons per kilogram). Identify the weapon that comes closest to this limit and state its yield-to-weight ratio. The accompanying tab-delimited-text file provides the following information for all publicly known weapons designed and built in the United States from 1945-1991:
    1. Designation (the "make and model" of the device)
    2. Type of device (bomb, warhead, artillery shell, or demolition munition)
    3. Weight in english pounds (1 kg = 2.2 lbs)
    4. Maximum explosive yield in kilotons of TNT
    Source: Sublette, Carey. Complete List of All US Nuclear Weapons. Nuclear Weapon Archive. 14 October 2006.

investigative

  1. Read this passage.

    The ultimate secret of the W-88 warhead, as with all nuclear bombs, is the mere fact that one kilogram of uranium, when completely fissioned, releases the energy equivalent of 18 thousand tons (18 kilotons) of TNT. Six kilograms of uranium would fit inside a can of soda pop. If the published descriptions are correct, the W-88 will fully fission about 26 kilograms of uranium, a liter and a half, or two wine bottles' worth. A softball bat made of uranium would weigh about 26 kilograms. The Hiroshima bomb reportedly had twice that much uranium-235, but it was only 2% efficient

    Source: Morland, Howard. The Holocaust Bomb: a Question of Time. Federation of American Scientists. 15 November 1999.

    Verify (in whatever order you wish) that…
    1. "[O]ne kilogram of uranium, when completely fissioned, releases the energy equivalent of 18 thousand tons (18 kilotons) of TNT."
    2. "Six kilograms of uranium would fit inside a can of soda pop."
    3. "[T]he W-88 will fully fission about 26 kilograms of uranium, a liter and a half, or two wine bottles' worth."
    4. "A softball bat made of uranium would weigh about 26 kilograms."