• bisby@lemmy.world
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      10 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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        10 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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          10 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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            10 days ago

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