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Hourglass Question

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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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#648958

On Monday, September 4, 2017 at 1:58:59 PM UTC-7, 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?
> -- 
> rhhardin@mindspring.com
> 
> On the internet, nobody knows you're a jerk.

Two reasons why moon sand clock will not work like an Earth's sand clock are #1 moon's force of gravity weaker,and #2 its sand is magnetic. I'm never in a hurry,and can live with just the turning of Earth. I think its nice when a Roster crows.That is kind of a sexy way of telling its time to get it up. TreBert

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#648973

On Wednesday, September 6, 2017 at 5:35:40 PM UTC-4, reber G=emc^2 wrote:
> On Monday, September 4, 2017 at 1:58:59 PM UTC-7, 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?
> > -- 
> > rhhardin@mindspring.com
> > 
> > On the internet, nobody knows you're a jerk.
> 
> Two reasons why moon sand clock will not work like an
> Earth's sand clock are #1 moon's force of gravity weaker,

Just a parameter to adjust for in the design.

>and #2 its sand is magnetic.

I had not heard that before. 

And #3 most of the dust has sharp edges.
(there is no erosion action to smooth out the
edges of the particles in the lunar soil.)

#3 is a big reason why the astronaut's footprints
were so clear. Dry sand on earth does not hold
the shape because the particles are generally smooth.

Ed

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#648978

> __There are more thgen Two reasons why__  >
<reber G=emc^2> <herbertglazier0@gmail.com> wrote:
"OK I'm lying.at 89 That is reality at my age."... & now
Bert just lied again since he lied for the past 89 years,
habitually and compulsively. The underlying reason for
that is that Glazier is an Ashkenazi
 >
kike, who shows signs of multiple & advanced genetic Jew
diseases  like (1) Tay-Sachs Disease which made him deaf,
(2) Familial Dysautonomia which causes Glazier's' sensory
nervous systems to malfunction, (3) Bloom Syndrome which
gave Bert his short stature & (4) Fanconi anemia - Type C
that gave Glazier his learning difficulties & mental
retardation.
 >
These maladies are present in 1 of 25 his ilk.
It's  effects & symptoms are manifest in that Bert got
kicked out of school in the 4th grade, and it is seen
in every post of Bert, like when Bert brags to be
 >
_______ Glazier, the Turd-man of Anaheim________
 >
with <http://tinyurl.com/SwineBert-s-WRONG-Predictions>
& being <http://tinyurl.com/Loudmouth-Glazier-8Feb2017>,
who is <http://tinyurl.com/The-Chosen-Graveyard-Vandal>
doing this <http://pbs.twimg.com/media/A8MGOU-CQAEaZw4.jpg>,
as he waits for <http://tinyurl.com/Swine-Glazier-s-Undertaker>
but refuses <http://tinyurl.com/Herbert-Glazier-s-Reprieve> &
then <http://tinyurl.com/Jew-Swine-Glazier-cries> as seen
in his <http://tinyurl.com/Blog-of-2-fecal-kikes-Mar2017> which
"it's tricky", Bert says, but "it fits" & "it's on the money". "Go Figure"

3.9 ----------------------------------------------------------

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#648979

On Monday, September 4, 2017 at 1:58:59 PM UTC-7, 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.

  Try "friction".

>  What's going on.

  Well, watch one for a while. You have a volume of stuff supported from below except for a relatively small hole in the supporting surface area. Naturally, the stuff will fall through that hole.

  The relationship between the size of the hole and the size of the bits, modulo friction between the bits, sets the flow rate. Reduce the friction to zero (as with a fluid) and the flow rate maximizes.
 
> 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?

  The key term you're looking for is "angle of repose". That's the slope of a pile of identical loose bits of anything that are not cohesive. As the sad falls the cone grows but at no time does the sand stabilize. Notice the shape of the hourglass prevents flow stoppage.


  Mark L. Fergerson

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