Path: csiph.com!weretis.net!feeder6.news.weretis.net!feeder.usenetexpress.com!feeder-in1.iad1.usenetexpress.com!border1.nntp.dca1.giganews.com!nntp.giganews.com!buffer1.nntp.dca1.giganews.com!nntp.earthlink.com!news.earthlink.com.POSTED!not-for-mail NNTP-Posting-Date: Mon, 04 Sep 2017 15:58:50 -0500 Message-ID: <59ADBEA8.5404@mindspring.com> Date: Mon, 04 Sep 2017 16:59:20 -0400 From: Ron Hardin X-Mailer: Mozilla 2.02 (WinNT; I) MIME-Version: 1.0 Newsgroups: sci.physics Subject: Hourglass Question Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 18 X-Usenet-Provider: http://www.giganews.com NNTP-Posting-Host: 71.50.213.116 X-Trace: sv3-dduyQVCHdxhW6cfMrsHi2OmfFGliFjpcsgFZAQ3ihqE4HHfeW/mSsiEyjd37zLVh3wROsfnyU1k5naL!F2L1YtERB8puUiAxYprDI1mwK8iztaIhtOVwIkX2IuYwQsSkOzd3TiqfwqlMQF3EjY2GSt1HGcxf!CD8nofs9Kro= X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 X-Original-Bytes: 1414 Xref: csiph.com sci.physics:648651 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? -- rhhardin@mindspring.com On the internet, nobody knows you're a jerk.