How does sand flow in the absence of gravity...?

Thomas

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"Thomas de Groot" <t.d### [at] internlDOTnet> wrote:
> How does sand flow in the absence of gravity...?
>
> Thomas

Why would there not be gravity in space?




Stephen

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Stephen nous apporta ses lumieres en ce 2007/11/12 09:04:
> "Thomas de Groot" <t.d### [at] internlDOTnet> wrote:
>> How does sand flow in the absence of gravity...?
>>
>> Thomas
> 
> Why would there not be gravity in space?
> Isn’t it gravity that keeps the stars and planets in orbit?
> Don’t
> 
> 
> Stephen
> 
> 
Absolutely, but when you are free floating in space, you don't feel any.
If you don't stand on a surface that is stationary relative to the dominent 
gravity, the sand could'nt flow, as the glass is affected in exactly the same 
amount as the sand.

-- 
Alain
-------------------------------------------------
When the people fear their government, there is tyranny; when the government
fears the people, there is liberty.
Thomas Jefferson

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Alain wrote:
> Stephen nous apporta ses lumieres en ce 2007/11/12 09:04:
>> "Thomas de Groot" <t.d### [at] internlDOTnet> wrote:
>>> How does sand flow in the absence of gravity...?
>>>
>>> Thomas
>>
>> Why would there not be gravity in space?
>> Isn’t it gravity that keeps the stars and planets in orbit?
>> Don’t
>>
>>
>> Stephen
>>
>>
> Absolutely, but when you are free floating in space, you don't feel any.
> If you don't stand on a surface that is stationary relative to the 
> dominent gravity, the sand could'nt flow, as the glass is affected in 
> exactly the same amount as the sand.
> 

The only solution to this problem I have found is that there would be 
sand at both the top and bottom of the glass.  This is due to any 
centrifugal forces caused by the spinning of the glass through space. 
You are all totally correct though.

Allen

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Alain <ele### [at] netscapenet> wrote:
> Stephen nous apporta ses lumieres en ce 2007/11/12 09:04:
> > "Thomas de Groot" <t.d### [at] internlDOTnet> wrote:
> >> How does sand flow in the absence of gravity...?
> >>
> >> Thomas
> >
> > Why would there not be gravity in space?
> > Isn’t it gravity that keeps the stars and planets in orbit?
> > Don’t
> >
> >
> > Stephen
> >
> >
> Absolutely, but when you are free floating in space, you don't feel any.
> If you don't stand on a surface that is stationary relative to the dominent
> gravity, the sand could'nt flow, as the glass is affected in exactly the same
> amount as the sand.
>

But an Hourglass is a mystical object and the sand is dragged along by the
passing of time.
I thought that everyone knew that :)


Stephen

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"Stephen" <mcavoys_AT_aolDOT.com> schreef in bericht 
news:web.47396cd7652ca94ac4e49fa40@news.povray.org...
>
> But an Hourglass is a mystical object and the sand is dragged along by the
> passing of time.
> I thought that everyone knew that :)
>
>
 Ah! We have a nice conundrum here, maybe with a bit of casuistry... :-)
... for, maybe, time is dragged along by the flow of the sand through the 
Hourglass!

Now, my solution would be to mount the hourglass in a rotating contraption 
to allow the sand to flow. And don't forget that:
'Twas brillig, and the slithy toves
Did gyre and gimble in the wabe:
All mimsy were the borogoves,
And the mome raths outgrabe.

Gyre and gimble are the keywords here to build such a contraption as I have 
in mind. Remember also the learned and comprehensive explanation of the 
above by Humpty Dumpty. And finally, look at:
http://en.wikipedia.org/wiki/Mimsy_were_the_Borogoves which tells of a 
haunting short story.


Thomas

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"Thomas de Groot" <t.d### [at] internlDOTnet> wrote:
> "Stephen" <mcavoys_AT_aolDOT.com> schreef in bericht
> news:web.47396cd7652ca94ac4e49fa40@news.povray.org...
> >
> > But an Hourglass is a mystical object and the sand is dragged along by the
> > passing of time.
> > I thought that everyone knew that :)
> >
> >
>  Ah! We have a nice conundrum here, maybe with a bit of casuistry... :-)
> ... for, maybe, time is dragged along by the flow of the sand through the
> Hourglass!

It could be, it could be indeed.
There is no denying it.

> Now, my solution would be to mount the hourglass in a rotating contraption
> to allow the sand to flow. And don't forget that:
> 'Twas brillig, and the slithy toves
> Did gyre and gimble in the wabe:
> All mimsy were the borogoves,
> And the mome raths outgrabe.
>
> Gyre and gimble are the keywords here to build such a contraption as I have
> in mind. Remember also the learned and comprehensive explanation of the
> above by Humpty Dumpty. And finally, look at:
> http://en.wikipedia.org/wiki/Mimsy_were_the_Borogoves which tells of a
> haunting short story.
>
>
> Thomas

Beware the vorpal vortex.

Stephen

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Here is the newest version.  Thanks for all the help so far, I think 
that changing the wood patterns helped out so much.  I probably never 
would have thought to do that.

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"Allen Dotson" <all### [at] emailnutscom> wrote in message 
news:473b43ce@news.povray.org...
> Here is the newest version.

     That looks so much better! Good work.

      ~Steve~

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Allen Dotson <all### [at] emailnutscom> wrote:
> Here is the newest version.  Thanks for all the help so far, I think
> that changing the wood patterns helped out so much.  I probably never
> would have thought to do that.

That's nice! The wood veins in the columns seem to imply that they are cut out
of the trunk center, which is unlikely in reality. You should move or rotate
the relevant texture, IMO.

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