• Theo@lemmy.world
    link
    fedilink
    English
    arrow-up
    28
    ·
    3 days ago

    For a water powered jetpack to lift a person it is estimated to need at least 100 gallons per minute, so similarly this could be what would be needed. Even for a second, a person’s bladder would need to be 1.6 gallons and expelled at a similar pressure. So not two seconds.

    • stinky@redlemmy.com
      link
      fedilink
      English
      arrow-up
      13
      ·
      edit-2
      3 days ago

      3.2 gallon bladder to achieve 2 seconds? And what kind of pressure are we talking, would it just like totally blow your dick off or what

      • Theo@lemmy.world
        link
        fedilink
        English
        arrow-up
        9
        ·
        3 days ago

        I mean a bladder can’t even hold a fifth of a gallon (more like 500ml) so we are already saying it is not possible but assuming there in the future is a human cyborg or a robot the same mass and volume as a human, they would need 60psi and 3.33 gal capacity for two seconds. This info is based on water powered jetpack companies that do this service. So, I did over look one thing: the jetpacks are dual and attached to your legs and they happen over water so not sure the rest of the calculations because I am not certain whether each jetpack has same psi for it to work or it is a combined psi and the water just comes from a hose so there is no capacity but the speed needs to be at least 100gpm.

        • Fermion@feddit.nl
          link
          fedilink
          arrow-up
          6
          ·
          3 days ago

          You may need to double the flow. With the water powered jet packs the water isn’t just being accelerated from a standstill. The water is first flowing up with close to the same speed and is redirected down. So the momentum exchange is twice what it would be if the water were stored in tanks with the flyer.

          • Theo@lemmy.world
            link
            fedilink
            English
            arrow-up
            3
            ·
            3 days ago

            Yea, I previously just learned that the psi depletes as soon as it leaves the contraption because there is much less pressure, and it is just speed coming out.

          • Theo@lemmy.world
            link
            fedilink
            English
            arrow-up
            1
            ·
            3 days ago

            That would be a challenge to find out. Because I would look for the material with the minimum durability, not just a metal tank, lol. Like what is the weakest material that can still withstand this type of thing.

            • stinky@redlemmy.com
              link
              fedilink
              English
              arrow-up
              1
              ·
              3 days ago

              Silicone Rubber

              Polyurethane (PU) Elastomers

              Thermoplastic Elastomers (TPEs)

              or traditional latex rubber

        • bradorsomething@ttrpg.network
          link
          fedilink
          arrow-up
          1
          ·
          3 days ago

          I remember learning a bladder begins to spasm at 600mL, so we could actually use this spastic pressure to help us levitate. In this paper, I propose…

      • Theo@lemmy.world
        link
        fedilink
        English
        arrow-up
        4
        ·
        edit-2
        3 days ago

        Well, for a minute of water jetpack it is 100 gpm, so I divided 100 by 60 seconds to get 1.6… for one second so two it would be 3 and a third gallons for two seconds assuming the right pressure of 60 psi.

          • Theo@lemmy.world
            link
            fedilink
            English
            arrow-up
            5
            ·
            3 days ago

            We can only go 15-20 psi. I was taking the scenario as theoretically there was a human anomaly out there that could handle it lol.