• bisby
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    3 days ago

    If it’s filled with stuff then it’s not filled with air. So it would be less buoyant. But yeah, probably harder to sink than people would guess

    • Paradux@lemmy.zip
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      3 days ago

      Bouyancy is based on how much water is displaced, not amount of air inside the container. 66x12x13=10,296 cubic inches. Fresh water density is about 0.0361 lb/in^3 so that case has to displace at least 372 lb to sink.

      Metric would be better for this but we’re talking about a stinger missile here.

      • Monument@lemmy.sdf.org
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        3 days ago

        I read your comment, then went to make a joke response to someone else about placing a vacuum chamber inside the case to reduce its buoyancy.
        This set off a several minute long internet hunt where I learned about Archimedes Principle, which you clearly describe. It turns out the only vacuum here is the one in my head.

        To wit: If placed inside the case, my empty head would reduce the buoyancy, but only by its own weight.
        A Pyrrhic victory.

        • Paradux@lemmy.zip
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          3 days ago

          My boy Archie figured some stuff out a long time ago! Unfortunately he didn’t get the story straight about phlogiston