# Centrifugal force and gravity..

Discussion in 'Science and Technology' started by Gingerbread Demon, Jul 8, 2020.

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Would a spinning component in the middle of a space station create gravity for people around the component in an adjoining room for example?

Say you had two rooms and both normally are in zero g but the moment the spinning part starts in between the two rooms would that introduce any kind of gravity?

Asking because that's the very thing they did in the movie Valerian and I don't think at all that would work but being a movie they probably had some technobabble answer.

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No, except that the station, which I assume is much more massive and extended than the spinning component, might tend to rotate slowly in the opposite direction to conserve angular momentum unless station-keeping gyros or RCS are used to counteract the motion. This does depend on the mechanism used to set the spinning component in motion though.

For example, a tip-rotor helicopter whose rotors are self-powered by tip jets or rockets does not feel this torque.

https://en.wikipedia.org/wiki/Tip_jet

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Ah.... OK I get that.

Just watching this silly movie and the intro to the movie they show the station being built and there's one part where a small ship docks with two sort of flanges on the outside and they start spinning, and once they spin everyone suddenly can walk without floating. I'll see if I can find the clip. It's a silly fun movie but that part got me wondering how that would even work since one force would have a reaction to it.

Scene takes place in 2030 you see the spinning ship dock and spin and suddenly they have gravity

Last edited: Jul 8, 2020

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Video not available in my country even using VPN to change my region to USA, Canada,... Do you know the approximate position during the movie? I have it on Blu-ray.

ETA: Found the sequence 2 minutes in - 2031, Gravity System Engaged - it's pure fantasy given what we currently know.

Last edited: Jul 8, 2020

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Oh I know that. Just it was amusing to see that that's how they did it. A spinning thing exerting force outside its immediate area.

6. ### XCV330★Premium Member

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I think they just put it in to look good. Sci fi movies come up with gravity methods to make production easier. Expanse tries harder than most to leave some realism.

Maybe the spinning devices were trying to set up a diamagnetic field to generate a kind of artificial gravity. That could sort of work but would require generating a tremendous magnetic field, sort of the opposite of levitating the frog and instead pushing it to one axis.

whether human beings could live in that kind of field, or how you would actually get anything done is another matter.

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I think the Expanse definitely is the most realistic TV scifi of recent times.

8. ### XCV330★Premium Member

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Alex is my most favorite space pilot of all time.

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Shame the actor felt, he had to screw it up, though.

10. ### XCV330★Premium Member

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Crap. Had no idea

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Roles can be recast - I hope it doesn't sink the series.

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What? Why would one role sink the show?

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It shouldn't but apparently some people don't like it if one of the main actors in a show has to be recast. Batwoman is another example. Even The Expanse is just another TV show. Doctor Who got over this problem in a rather clever way back in the 60s, of course...

14. ### XCV330★Premium Member

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Cas Anvar was just a very good actor who has turned what might otherwise be a bland role into something special. Anyway, filming from what I've heard already wrapped up and season 5 will come out in Feb