• HappyFrog
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    13 hours ago

    The lump would still have about 14% uranium still in it. (If my understanding of half-life is correct)

    • PieMePlenty@lemmy.world
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      13 hours ago

      Afaik its always going to have some parts of uranium right? 50% after one half life, 25% after two half lives and it will keep on halving practically forever (or till the last atom decays). In the end it comes down to when you consider it a negligible amount.

      • JayDee@lemmy.sdf.org
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        10 hours ago

        I mean, yes, that’s how it would work if there were an infinite number of atoms in the piece. There’s a finite amount, though, so eventually there will be a point when all the atoms have completely decayed.

        All models are wrong, but some are useful.

      • HappyFrog
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        10 hours ago

        Yeah, thats what I was using to get 14%.

        2billion years is about 2.8 halflives, so I calculated (1/2)^2.8 ~ 0.14.

      • FuglyDuck@lemmy.world
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        13 hours ago

        after a certain point, you’re going to get to where you have to split an atom or two.

        fairly sure that’d be far less exciting than normal.

        Edit: i decided to try and figure out how long that would take… and per usual the law of large numbers caused my eyes to glaze over.

          • FuglyDuck@lemmy.world
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            55 minutes ago

            I mean I didn’t get that far, I lost track of how many zeroes were in the half-life.

            (It’s 704ish million, right?)