• 58008@lemmy.worldOP
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      1 年前

      Thank you, really interesting!

      On a side note, I always through Stack Exchange was just for computery stuff. Didn’t know it covered everything!

    • BearOfaTime@lemm.ee
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      1 年前

      Very interesting, but I don’t see how replacing the same volume of air in our lungs with helium doesn’t make you lighter. It’s the same volume, so the volume displacement zeroes out in any equation - I think that poster may mean as compared to empty lungs. Even then I think they’re mistaken - otherwise a blimp/balloon wouldn’t work, as it too is displacing air around itself, and increasing in volume.

      • SmoothIsFast@lemmy.world
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        1 年前

        Helium by volume is lighter than air. That metric is called density.

        So if you displace the volume in your lungs with helium that weighs less than the air that’s usually there, you will weigh less.

        Physics!

  • SkyNTP@lemmy.ml
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    1 年前

    Let me take this a step absurdly far:

    You may be slightly more buoyant (and therefore apply less force on a scale) everytime you breath in. It’s not the presence of air that has this effect, it’s the decrease in density of your total body (mass/volume) that has that effect. (Helium just contributes a fractional more difference in density compared to air, but how much you breath in probably matters much more than what you breath)

    Except, maybe not. Because the air you breath in partially dissolves in your blood. Dissolved matter does not decrease density, rather the opposite: it packs tightly into the voids, increasing mass for the same volume.

    How much of an effect this has is hugely debatable, probably depends on a dozen biological and circumstantial factors, and this is where my knowledge ends. But it’s fun to imagine.

    However, if you can imagine inhaling but holding your breath at the same time, creating a vacuum in your lungs, then yes, you would be more buoyant, even more than inhaling helium, and the scale would read slightly less.

  • johsny@lemmy.world
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    1 年前

    Weigh less, but your mass slightly increases, so maybe it cancels out.

  • Boomkop3@reddthat.com
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    1 年前

    No, you don’t. You’re adding more mass to your body. However: not as much as you would when breathing air

    • Hyperlon@lemmy.world
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      1 年前

      You are adding more mass to your body, but you are also decreasing your body’s density. So this should in fact make you lighter on the surface of the earth.

      • Boomkop3@reddthat.com
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        1 年前

        Buoyancy is a thing, even in the regular old earth’ atmosphere. I figured to mention it but I didn’t want to give too complex of an answer