In sci-fi with “spinning” ships to make gravity, how does someone drop something and it lands at their feet?

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This fogs my brain every time I watch one of these shows and I feel like maybe I’m completely misunderstanding the physics.

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You’re in a “ring” ship. The ring spins. You’re standing on the inside of the ring so it takes you along with it, and the force created “pins” you to the floor, like a carnival ride. Ok, fine.

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But that’s not gravity, and it’s not “down”. Gravity is acceleration, so what keeps the acceleration going in the ring ship is that you are constantly changing your angular momentum because you’re going in a circle. Ok, so when you let go of something, like a cup or a book, wouldn’t it go flying towards the floor at an angle? If you jumped wouldn’t you look like you rotated a little before you hit the ground, because you’d, for that moment, be continuing the momentum of your angular velocity from when you left the floor and the room would continue on it’s new, ever turning, course?

Wouldn’t it kind of feel like walking “uphill” one direction and “downhill” the other, with things sliding about as the room “changed” direction constantly?

Am I just COMPLETELY missing this idea and creating a cause and effect that doesn’t exist?

In: Physics

25 Answers

Anonymous 0 Comments

Yes, all those things would happen. To mitigate them, you have to use a bigger ring. In something like the ship from 2001, the effect would be noticeable. In something with a half kilometer or so radius, you could do an experiment in your home to measure the effect. Beyond a few kilometers radius, it gets hard enough to detect that you’d need lab equipment. You definitely wouldn’t notice it day-to-day.

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