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How much power will 10 grams of plutonium produce?

  1. Dec 1, 2008 #1
    How much power will 10 grams of plutonium produce in megatons if 100% of the 10 grams is converted into energy?
  2. jcsd
  3. Dec 2, 2008 #2

    The thing is... to do this. You would essentially need an antimatter-matter reaction.

    So plutonium is more or less a unneccessary component. You could just plain hydrogen. You simply need mass. Then you need 1:1 ratio so 10 grams of matter + 10 grams of matter.

    So the M is double the M.

    So basically...

    0.02Kilograms * 300,000,000 * 300,000,000 = Joules.
    1,800,000,000,000 Kilojoules

    Then 1 megaton = 1 million tons.

    So 1,800,000,000/1,000,000

    So assuming I calculated correctly :)

    1,800 megatons

    Now you can go with nuclear bomb... but it is ~1% efficient.
    Largest nuclear bomb I am familiar with was 50megatons.

    So the 100% efficiency of antimatter-matter is amazing.
  4. Dec 2, 2008 #3


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    A "megaton" is not what you would think. It is an energy unit, corresponding to the blast energy of one million ton of a standard military explosive.

    A megaton corresponds to about 4.184 PJ (peta joule), 4.184E15 J.

    1 kg of matter + 1 kg of antimatter releases about 43 Megaton, which is comparable to the Tsar Bomba that the Soviets blew up http://en.wikipedia.org/wiki/Tsar_Bomba

    So 10 g + 10 g will give you 430 Kiloton, which is what a medium-size nuclear weapon will give you (about 30 times the Hiroshima bomb).
  5. Dec 2, 2008 #4
    I'm not sure how you put anti matter and matter in the same device, Does anyone know how?
  6. Dec 2, 2008 #5


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    The000Agent: you can store the anitmatter in a magnetic field cage, and then when detonation, you just shut of the magnetic cage.

    Vanesch, with current rate at producing antiprotons, it will take several million of years even to procoude 1gram ;-)
  7. Dec 2, 2008 #6
    First of all, your question is very vague. Let me try to fill in the blanks.

    Since plutonium is mentioned, I'm guessing that you're talking about old-fashioned nuclear decay, not matter-antimatter annihilation.

    There are two industrial isotopes of plutonium, 238 and 239. 238 is used as a power source on space probes and 239 is used as a fuel in nukes. Since you want the answer in megatons, and megatons are a nuke term, you must be thinking about 239.

    One gram of plutonium-239 can produce 70 GJ (7E10 J) of energy when fully fissioned. That's around 15 tons. 10 grams = 150 tons.

    In a nuclear explosion, you never get 100% or near 100% efficiency. Your plutonium is dispersed by the explosion before it has a chance to fission fully. Well-designed bomb could have 25% efficiency. Your 10 grams would be the equivalent of 40 tons of TNT.
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