this post was submitted on 22 May 2024
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xkcd

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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.

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[–] TimewornTraveler@lemm.ee 9 points 6 months ago (8 children)

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

[–] renormalizer@feddit.de 4 points 6 months ago (2 children)

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 1 points 5 months ago (1 children)

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

[–] renormalizer@feddit.de 1 points 5 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.

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