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Groups > sci.physics > #648936
| Message-ID | <59B040CE.429@mindspring.com> (permalink) |
|---|---|
| Date | 2017-09-06 14:39 -0400 |
| From | Ron Hardin <rhhardin@mindspring.com> |
| Newsgroups | sci.physics |
| Subject | Re: Hourglass Question |
| References | <59ADBEA8.5404@mindspring.com> |
Ron Hardin wrote: > > An old question from the 1970s that I never > figured out. > > What governs the speed of flow of an hourglass? > > I mean what principle. What's going on. > > It's not viscosity (no transport of x momentum in > the y direction etc.) > > It seems like it's the time it takes something to > call out of a lockup condition and clear the mess, > leaving it up to the next lockup condition, but > what the hell equation is that? Try this start: the sand above the hole consists of locked up unstable structures, each stabilized by the structure below it. The one at the bottom goes unstable and falls, freeing the one above to begin going unstable. So there a distance between structures, an instability growth time to collapse. -- rhhardin@mindspring.com On the internet, nobody knows you're a jerk.
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Hourglass Question Ron Hardin <rhhardin@mindspring.com> - 2017-09-04 16:59 -0400
Re: Hourglass Question Serg io <invalid@invalid.com> - 2017-09-04 17:53 -0500
Re: Hourglass Question Double-A <double-a3@hush.com> - 2017-09-05 13:44 -0700
Re: Hourglass Question benj <benj@nobody.net> - 2017-09-05 19:34 -0400
Re: Hourglass Question "reber G=emc^2" <herbertglazier0@gmail.com> - 2017-09-06 14:22 -0700
Re: Hourglass Question benj <benj@nobody.net> - 2017-09-06 18:21 -0400
Re: Hourglass Question Serg io <invalid@invalid.com> - 2017-09-06 18:18 -0500
Re: Hourglass Question hanson <hanson@quick.net> - 2017-09-06 15:35 -0700
Re: Hourglass Question Double-A <double-a3@hush.com> - 2017-09-07 13:06 -0700
Re: Hourglass Question Serg io <invalid@invalid.com> - 2017-09-07 16:44 -0500
Re: Hourglass Question Double-A <double-a3@hush.com> - 2017-09-08 13:34 -0700
Re: Hourglass Question "reber G=emc^2" <herbertglazier0@gmail.com> - 2017-09-08 15:53 -0700
Re: Hourglass Question "hanson" <hanson@quick.net> - 2017-09-08 17:36 -0700
Re: Hourglass Question Double-A <double-a3@hush.com> - 2017-09-11 14:41 -0700
Re: Hourglass Question "reber G=emc^2" <herbertglazier0@gmail.com> - 2017-09-09 13:31 -0700
Re: Hourglass Question "hanson" <hanson@quick.net> - 2017-09-09 14:32 -0700
Re: Hourglass Question Ron Hardin <rhhardin@mindspring.com> - 2017-09-06 14:39 -0400
Re: Hourglass Question Serg io <invalid@invalid.com> - 2017-09-06 14:01 -0500
Re: Hourglass Question Ron Hardin <rhhardin@mindspring.com> - 2017-09-06 18:36 -0400
Re: Hourglass Question jimp@specsol.spam.sux.com - 2017-09-06 19:26 +0000
Re: Hourglass Question "reber G=emc^2" <herbertglazier0@gmail.com> - 2017-09-06 14:35 -0700
Re: Hourglass Question Edward Prochak <edprochak@gmail.com> - 2017-09-06 15:32 -0700
Re: Hourglass Question hanson <hanson@quick.net> - 2017-09-06 15:44 -0700
Re: Hourglass Question "nuny@bid.nes" <alien8752@gmail.com> - 2017-09-06 15:50 -0700
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