https://xkcd.com/2935

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

  • @[email protected]
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    41 month 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.

    • @[email protected]
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      11 month ago

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

      • @[email protected]
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        11 month 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.