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Posers and Puzzles

Posers and Puzzles

  1. 24 Jan '09 04:39
    Watching 2001: A Space Odyssey got me thinking. If you're running around the inside of a cylinder along the circumference in space, is it essentially the same as running on a flat surface in terms of energy it takes to run?

    The guy was wearing some kind of shoes that kept him glued to the ground, so he wasn't floating around.

    Any ideas?
  2. 24 Jan '09 07:48
    Originally posted by prosoccer
    Watching 2001: A Space Odyssey got me thinking. If you're running around the inside of a cylinder along the circumference in space, is it essentially the same as running on a flat surface in terms of energy it takes to run?

    The guy was wearing some kind of shoes that kept him glued to the ground, so he wasn't floating around.

    Any ideas?
    A runner in a cylinder in space doesn't have to have 'glue shoes'. The 'centrifugal force' makes the job.

    But (depending of the radius of the cylinder) the coriolis effect makes you feel that you are falling farward all the time. You have to compensate for this by leaning backwards. This makes the runner look funny.
  3. 24 Jan '09 09:16
    Originally posted by FabianFnas
    But (depending of the radius of the cylinder) the coriolis effect makes you feel that you are falling farward all the time. You have to compensate for this by leaning backwards. This makes the runner look funny.
    Unless perhaps, you ran the other way?
  4. 24 Jan '09 12:03
    Originally posted by Meadows
    Unless perhaps, you ran the other way?
    Samo samo.
  5. 24 Jan '09 15:39
    Originally posted by FabianFnas
    A runner in a cylinder in space doesn't have to have 'glue shoes'. The 'centrifugal force' makes the job.

    But (depending of the radius of the cylinder) the coriolis effect makes you feel that you are falling farward all the time. You have to compensate for this by leaning backwards. This makes the runner look funny.
    But which way will the toilet flush?
  6. Standard member wolfgang59
    Infidel
    25 Jan '09 19:39
    Originally posted by prosoccer
    Watching 2001: A Space Odyssey got me thinking. If you're running around the inside of a cylinder along the circumference in space, is it essentially the same as running on a flat surface in terms of energy it takes to run?

    The guy was wearing some kind of shoes that kept him glued to the ground, so he wasn't floating around.

    Any ideas?
    Depends on size of cylinder and speed of rotation. We are all running on the outside of a sphere but we all percieve it as flat.

    Coriolis effect only matters for small cylinders,

    How small? ... dunno .. somebody work it out!

    In terms of energy I would make an educated guess that the work done (energy) is equivalent to Force x Distance so that the more you perceive the surface as flat the closer it would be to actually running.
  7. 26 Jan '09 11:20
    Originally posted by wolfgang59
    Depends on size of cylinder and speed of rotation. We are all running on the outside of a sphere but we all percieve it as flat.

    Coriolis effect only matters for small cylinders,

    How small? ... dunno .. somebody work it out!

    In terms of energy I would make an educated guess that the work done (energy) is equivalent to Force x Distance so that the more you perceive the surface as flat the closer it would be to actually running.
    The flatter the cylinder was/looked (i.e. if a big one) would lead to a loss of certipetal force on the feet vs the floor and so wouldn't the runner drift away?
  8. Standard member forkedknight
    Defend the Universe
    26 Jan '09 22:40
    Originally posted by FabianFnas
    A runner in a cylinder in space doesn't have to have 'glue shoes'. The 'centrifugal force' makes the job.

    But (depending of the radius of the cylinder) the coriolis effect makes you feel that you are falling farward all the time. You have to compensate for this by leaning backwards. This makes the runner look funny.
    Centrifugal force doesn't exist, or at least not in the way you used it there; I'm not sure if you were trying to make a funny...

    It's centripetal force.
  9. 27 Jan '09 01:56
    Originally posted by divegeester
    The flatter the cylinder was/looked (i.e. if a big one) would lead to a loss of certipetal force on the feet vs the floor and so wouldn't the runner drift away?
    couldn't they just compensate by having the cylinder rotate faster?
  10. 27 Jan '09 02:02
    Originally posted by forkedknight
    Centrifugal force doesn't exist, or at least not in the way you used it there; I'm not sure if you were trying to make a funny...

    It's centripetal force.
    pretty sure this was how he was using the idea of "centrifugal force," though you're right - as newtonian physics would define "force," it doesn't really exist. however, within the perspective of the rotating system, it has real, physical, perceptible meaning.

    http://www.newton.dep.anl.gov/newton/askasci/1993/physics/PHY6.HTM
  11. 27 Jan '09 05:46
    Originally posted by forkedknight
    Centrifugal force doesn't exist, or at least not in the way you used it there; I'm not sure if you were trying to make a funny...

    It's centripetal force.
    That's why I used quote/unqutoe around the word 'centrifugal' force just to avoid such a comment. I thought you would understand what I meant.

    'Centrifugal' force cannot be interchanged with 'centripetal' force. You know that...
  12. Subscriber sonhouse
    Fast and Curious
    27 Jan '09 08:59
    Originally posted by FabianFnas
    A runner in a cylinder in space doesn't have to have 'glue shoes'. The 'centrifugal force' makes the job.

    But (depending of the radius of the cylinder) the coriolis effect makes you feel that you are falling farward all the time. You have to compensate for this by leaning backwards. This makes the runner look funny.
    If it's a cylinder a thousand meters in diameter, you probably wouldn't notice the difference between that and gravity. But wouldn't the centripital effect get greater the faster you ran?
  13. 27 Jan '09 10:31
    Originally posted by forkedknight
    Centrifugal force doesn't exist, or at least not in the way you used it there; I'm not sure if you were trying to make a funny...

    It's centripetal force.
    http://xkcd.com/123/
  14. Standard member PBE6
    Bananarama
    27 Jan '09 14:40
    Originally posted by mtthw
    http://xkcd.com/123/
    Teh lulz