https://xkcd.com/2935

Alt text:

I can’t believe they wouldn’t even let me hold a vote among the passengers about whether to try the loop.

  • Hamartiogonic
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    6 months ago

    Next try to calculate what it would actually mean to make that much water follow a path like that. My guess is, it’s going to get very spicy.

    • towerful@programming.dev
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      6 months ago

      The xkcd explained brushes near it.

      Many of the passengers would suffer extreme injuries from the changes of velocity (up to 230 mph based on a loop radius of 3 x ship length) and rotation (unlike rollercoasters, or even airplanes during simple take-off and landing, passengers aren’t normally strapped down).

    • naeap
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      6 months ago

      Thanks, you just gave me something to watch :-)

      (Although I’ll finish my current season of doctor who first)

  • 🇰 🌀 🇱 🇦 🇳 🇦 🇰 ℹ️@yiffit.net
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    6 months ago

    How fast would the water have to be traveling for this to actually work? Pretty sure there was a waterslide built with a loop once and it infamously didn’t work, but those work on gravity alone. With enough pressure it should be able to loop, right? Or would it just get wonky because it’s a fluid? 🤔

    I feel like this could be one of those things that works perfectly if you make a small model, but won’t ever scale up due to reasons.

  • TimewornTraveler@lemm.ee
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    6 months ago

    Holy shit I wonder if it’s even humanly possible to build one of these in the ocean for any size ship.

      • Dozzi92@lemmy.world
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        6 months ago

        Cruise ship or bust.

        And it’s just a drawing but I’m trying to realize it in actual size. Cruise ships are huge, pushing 250 or so feet out of the water. That’s considered a high-rise in the construction world.

        Now I look at that loopdy-lopp and say hey, that boat could fit. I’m ignoring all the other physics and shit and just Matchbox car’g that boat through that loop. That makes that loop like, what, 1000 feet? And that is ignoring the structure beneath the surface, and also the other dimensions of this, and the sheer velocity and volume of water.

        So I’m gonna call this one a hard maybe. Perhaps if the world could set aside it’s differences, we could do a sort of space race, but instead a ship flip, or a boat float, or some other rhyme.

    • renormalizer@feddit.de
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      6 months ago

      You just have to go fast enough. The minimum speed keeping you from falling out of a circular loop is sqrt(gr), with gravitational acceleration g and loop radius r. 10m radius requires 36km/h, which might be suitable for a Jetski. Larger ships need bigger loops to physically fit, and consequently larger speeds. It’s quite surprising, but a monstrous 100m radius loop needs less than 120km/h.

      • TimewornTraveler@lemm.ee
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        6 months ago

        so mass doesn’t factor into the equation??? a Jetski made from aluminum would need the same speed as from osmium?

        • renormalizer@feddit.de
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          6 months ago

          I think so. At the apex of the loop gravity balances centrifugal force, Fg = Fc, when going the minimal speed necessary to get through the loop. Fg = m g, Fc = m v^2 / r. So mass m drops out of the equation.