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View Full Version : a minor note...



edibobb
2004-Mar-04, 05:33 AM
In the coriolis page (bathtub draining), it mentions that if you drop a rock from the axis of a rotating space station, it will seem to fall in a curve opposite the direction of rotation.

Won't it really just sit there at the axis when you drop it, unless you give it a little toss?

... and furthermore, I really like this site!

xbck1
2004-Mar-04, 04:22 PM
We like this site too! Welcome. :D

Kaptain K
2004-Mar-04, 05:49 PM
In the coriolis page (bathtub draining), it mentions that if you drop a rock from the axis of a rotating space station, it will seem to fall in a curve opposite the direction of rotation.

Won't it really just sit there at the axis when you drop it, unless you give it a little toss?

Well, yes! If:

1) You release it exactly on the centerline.

and

2) You release it with exactly zero radial velocity.

Even then, eventually a stray breeze will blow it off center and it will fall.

Welcome to the board! =D>

The Bad Astronomer
2004-May-10, 01:02 AM
Hey, edibobb, it's about time you dropped by here! I've been reading your junkmail for two years or more. Everyone, go to his website, xpda.com (http://www.xpda.com) and poke around, It's fun.

About the rock: if there were no air in the station, then yeah, it would appear to sit there. But the air will be spinning with the station, and provide a force which will move the rock down, which in this case is really out, away from the central axis. So it appears to fall.

I guess the motion might be pretty complicated. A dense rock would appear to curve more than a less dense rock, because it is affected by air resistance less. I'm not sure, to be honest. Sounds like something we need to verify via experiment!