• March 29, 2021, 2:16 p.m.

    I read somewhere an estimate of the dimension of this cylinder.
    A diameter of 8km, approx 5 miles.. and a rotation speed of 2 revolutions per minute. (Sounds unlikely)
    Now, what if you jumped up, (towards the center of the cylinder) Would you just float away?
    What if you dropped something? ( I suspect the gravitational sensation you feel would only work if you are in fysical connection to the ground).
    If my suspection is righ then you cant run.. as soon as both your feet are off ground you would:
    a) float off, b) hit something that is fixed to the ground, c) both.
    Living under these conditions would be ...difficult?
    And if this is correct.. there would soon be a ton of debris floating around inside this cylinder.
    How would weather be, you cant get rain, water would not be able to fall, so having green patches or forest seems unlikely.
    If Im wrong, there will be a pull towards ground if you are near enough, the ground would not need to spinn, an outher ring would spinn, and the inner be fixed and you would not need to think of the Coriolis effect.
    Has anyone any math for this?

  • April 3, 2021, 9:43 p.m.

    I think that's a bit fast for that diameter. All the math you need is here: en.wikipedia.org/wiki/Centripetal_force

    No you would not float away. Remember even if you jump up, you are still moving at about the same speed as the ground under your feet, so you will 'fall' back down.

    To a stationary (non-spinning) outside observer, it would look as if you were flying at a tangent inside the cylinder, which would take you on a collision course back to the inside of the curved cylinder wall.

    On the other hand, if you could run against the direction of the spin as fast as the cylinder is spinning, then you would end up in free fall and then you really would start floating. For a cylinder that big you'd have to run 2 * pi * 4km * 2rpm = 50.2654824574 kilometers per minute I think. You might need a jet plane.

    Even so, if there is any air inside the cylinder then air drag would pull you back up to cylinder speed again and you would go back to 'falling'.

  • April 7, 2021, 10:09 p.m.

    So as I get it, the air itself and the «tangent motion» will provide enough drag on your body to keep you at the ground.
    Its hard to grasp the forces and calculations. But I think your explanation is good.
    Thank you for the ansver! 👍