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I have been trying hard to understand how Artificial Gravity is produced by Rotating a satellite around its own axis.

Thus far, I have understood (probably wrong) that as a satellite is spun, walls of satellite provide centripetal force to occupants and it acts as a normal reaction. However it is yet not clear to me with any site or book that with what acceleration it should spin. Of course whatever the centripetal acceleration is, it would provide a normal force to occupants (maybe little but it will) but I think since satellite is in free fall, occupants are accelerating at the same rate as satellite and therefore, in order to provide a normal reaction to the occupants the satellite ought to spin with same acceleration as it is orbiting with around the Earth (definitely not $g$).

I am still confused whether I am right or wrong because I have read on this site that satellite should spin with acceleration equals $g$ so that a normal force is provided to occupants as is it on Earth.

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A spinning space station does not provide artificial gravity away from Earth, it provides artificial gravity toward the center of the station. The first effect the spinning surface has on an occupant is to provide a tangential acceleration through friction. Then, because the tangential direction runs into the wall, the occupant is "thrown against the wall" (similar to when you take a sharp turn in an automobile and are thrown to one side of the vehicle) and then the wall provides a normal force toward the center of rotation that simulates gravity.

The spinning surface doesn't generate an "artificial gravity" itself, in the sci-fi sense: if you were somehow able to get to the center and stop there, you could hover there because then it's the usual space station weightlessness (like on the ISS). Or if you could jump up and use a jet pack or whatnot to reverse your tangential velocity to zero, you could hover as the floor spins beneath you. Of course, then there would be no reason to call the floor "down" anymore; you're just floating in space, with a cylinder spinning around you.

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  • $\begingroup$ How does friction come into play? $\endgroup$
    – user104909
    Commented Jan 27, 2016 at 13:37
  • $\begingroup$ Wikipedia article suggests that the force which drives occupants outwards on rotation is centrifugal force. $\endgroup$
    – user104909
    Commented Jan 27, 2016 at 13:47
  • $\begingroup$ There's also an issue of Coriolis acceleration that comes about from the rotational motion, not gravity. For the smaller space station this force would be greater giving an unusal experience of gravity as compared to what we experience on earth. As you move about the station one would feel sideways pulling forces making it difficult to walk in a straight line. A bigger station would help minimize these forces. $\endgroup$
    – docscience
    Commented Jan 27, 2016 at 14:54
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    $\begingroup$ @SufyanNaeem nothing "drives occupants outwards" radially. The move inertially in straight lines until something pushes them out of a straight line. In this case, they are moving on a straight tangential path until the wall pushes them inward; even then, if the wall only pushed them for a moment, it would result in a new inertial, tangential path. The continuous acceleration toward the center (centripetal, not centrifugal) is what causes the feeling of gravity. $\endgroup$
    – Asher
    Commented Jan 27, 2016 at 14:58

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