Naked Science Forum
General Science => General Science => Topic started by: neilep on 21/08/2006 18:40:57
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Dearest Robust Head Dwellers Where Nimble & Quick Brains Find Their Abode.
See this bottle ?..nice eh ?..notice how it complements the tiles...ahhh !!...I am at one with this bottle !!
But what I want to know is the science behind the facts that it takes 15 seconds to fill when held upright in the bath with six inches of water above it and only ten seconds to empty when held upside down above the water.
I did it five time...each time perhaps there was a second either way from both filling and emptying.
I tried to get it to fill quicker and empty slower by using harsh language but it did not work !
So, why does it empty quicker than it fills ?
This is what occupies my thoughts today !!
Whomsoever fulfills this science for me will win a hug and a shared bath !!...and I will show you how to make your own bubbles in the bath without bottles too !![:)]
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fimg.photobucket.com%2Falbums%2Fv280%2Fwithdrawnmist%2FDSC02647.jpg&hash=d73875626f1e9c6df9eb8283cdc1a99b)
A nice bottle that I am at one with !
Source: My Bathroom
Men are the same as women, just inside out !
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What orientation were you holding the bottle in when you were filling and emptying it?
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quote:
Originally posted by daveshorts
What orientation were you holding the bottle in when you were filling and emptying it?
On the vertical for both filling and emptying Dave ..thanks.
Men are the same as women, just inside out !
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And some poor scallop had to suffer the indignity, of being used as a mould to make your bathroom asthetically pleasing, did it ?the RSPCS should hear about this, i bet the scallop dont even get royalties ! damn those scallop dredgers ![V]
all in one place
http://www.p-r-travel.co.uk
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Im guessing that when filled underwater the air escaped in bursts but when emptied it was a pretty steady stream yeah? this is probably caused by the air all wanting to escape at once and in effect blocking the entrance of the water which means there are stages to the filling ie air escapes, water enters, air escapes, water enters ect but when inverted the air is much easier than the water to enter in small amounts so the two processes can work simultaniously and empty the bottle that much faster.
Im not sure Ive explained this very weel so next time take a clear bottle and you should see what im talking about.
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George you have been able to explain to an extent, the air already fills the bottle and struggles to get out of the bottle as water tries to enter. Neilep, try using a container of wider opening, you would observe that the rate of filling and emptying the container is expected to be relatively equal.
lets keep trying the untried since the birth of science innovations have been like toy but their impacts have rocked the world
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THANK YOU THAYO....THANK YOU SHARKEY/.... (oh..Ta Ray [:)])
When holding the bottle vertically upside down, it still ' glug glugging ' out !..it is not s steady stream but I presume what what you have said that it probably is more an easy flow than filling it up. I think you HAVE explained it well Sharkey !
I originally thought that perhaps the weight of the water in concert with gravity was a stronger force than the lightness and buoyancy of the air when filling up.
THAYO..I will try a bottle with a bigger spout. I agree I think it will offer equilibrium the larger the spout is
Men are the same as women, just inside out !
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Try turning the bottle just slightly when emptying just enough that there is no gluping, as it hits the shoulders of the bottle. that would slow the empting. Just turn it to ists side so it comes out smoothly, not upside down as then the water is hitting the shoulder first! I am curious as to weather without that force if it will pour out quicker and smoother, you know, On its side!!! Whoops, I was thinking backwards. I guess you were wanting to know why it fills so slow not empys so fast. Try filling it on its side!!
Karen
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Thank you Karen,
They are all fantastic points and I will try them all out.
But lol[:)]...the premise of my question was specific to the science of why the bottle fills and empties exactly as I have described. I do realise that changing the orientation of the bottle will give different results.
Perhaps I should have made it clear that the bottle is one of the kids 'bath-play ' bottles . I just found it interesting when observing this game ,when one of them was counting, as they played with it. Of course..I had to have a go !!
Men are the same as women, just inside out !
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Vortices & turbulence may explain your observation.
Here is an aerodynamic analogy:-
" Vortices last longer in calm air, and atmospheric turbulence hastens their decay. Decay is the dying out of eddies. All aircraft produce wake vortices—much like two small horizontal tornadoes trailing behind the wing tips. The larger and heavier the plane is, the stronger the wake. That means small aircraft that follow larger ones can encounter turbulence if they are not kept far enough apart. The turbulence can be severe enough to cause a plane to crash. "
http://media.nasaexplores.com/lessons/01-071/5-8_1.pdf
The water in your "filling" bottle was more turbulent than when "emptying".
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Himanshu1khatri's post gave me this idea.
While filling, water breaches the meniscus that forms about the mouth of the clam-bottle. It is a tough little piece of surface-tension that quickly re-forms itself.
The water exits through the same diametre mouth, but more quickly.
I think that what governs the water's exit is the meniscus formed on the inside. The emptying maniscus is just as tough as the filling maniscus, but it is now the size of the inner bottle's cross-sectional area. Being larger in area means that it is not so quick to re-form itself. Water exits more quickly.
Four of five "Glugs" and the bottle is empty. The end of each 'Glug" represents the re-forming of the inner meniscus.
Mike
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Excellent Info ROBERT.many thanks..
and Jysk (Mike) ....I am impressed !!...this young lad has some excellent ideas.
Men are the same as women, just inside out !
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quote:
Originally posted by ROBERT
Vortices & turbulence may explain your observation.
Here is an aerodynamic analogy:-
" Vortices last longer in calm air, and atmospheric turbulence hastens their decay. Decay is the dying out of eddies. All aircraft produce wake vortices—much like two small horizontal tornadoes trailing behind the wing tips. The larger and heavier the plane is, the stronger the wake. That means small aircraft that follow larger ones can encounter turbulence if they are not kept far enough apart. The turbulence can be severe enough to cause a plane to crash. "
http://media.nasaexplores.com/lessons/01-071/5-8_1.pdf
The water in your "filling" bottle was more turbulent than when "emptying".
Right Click. Save as.
Thanks
Steven
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In a time of universal deceit - telling the truth is a revolutionary act.
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Himanshu1khatri's post gave me this idea.
While filling, water breaches the meniscus that forms about the mouth of the clam-bottle. It is a tough little piece of surface-tension that quickly re-forms itself.
The water exits through the same diametre mouth, but more quickly.
I think that what governs the water's exit is the meniscus formed on the inside. The emptying maniscus is just as tough as the filling maniscus, but it is now the size of the inner bottle's cross-sectional area. Being larger in area means that it is not so quick to re-form itself. Water exits more quickly.
Four of five "Glugs" and the bottle is empty. The end of each 'Glug" represents the re-forming of the inner meniscus.
Mike
-
Himanshu1khatri's post gave me this idea.
While filling, water breaches the meniscus that forms about the mouth of the clam-bottle. It is a tough little piece of surface-tension that quickly re-forms itself.
The water exits through the same diametre mouth, but more quickly.
I think that what governs the water's exit is the meniscus formed on the inside. The emptying maniscus is just as tough as the filling maniscus, but it is now the size of the inner bottle's cross-sectional area. Being larger in area means that it is not so quick to re-form itself. Water exits more quickly.
Four of five "Glugs" and the bottle is empty. The end of each 'Glug" represents the re-forming of the inner meniscus.
Mike
-
Excellent Info ROBERT.many thanks..
and Jysk (Mike) ....I am impressed !!...this young lad has some excellent ideas.
Men are the same as women, just inside out !
-
quote:
Originally posted by ROBERT
Vortices & turbulence may explain your observation.
Here is an aerodynamic analogy:-
" Vortices last longer in calm air, and atmospheric turbulence hastens their decay. Decay is the dying out of eddies. All aircraft produce wake vortices—much like two small horizontal tornadoes trailing behind the wing tips. The larger and heavier the plane is, the stronger the wake. That means small aircraft that follow larger ones can encounter turbulence if they are not kept far enough apart. The turbulence can be severe enough to cause a plane to crash. "
http://media.nasaexplores.com/lessons/01-071/5-8_1.pdf
The water in your "filling" bottle was more turbulent than when "emptying".
Right Click. Save as.
Thanks
Steven
_______________________________________________________________
In a time of universal deceit - telling the truth is a revolutionary act.
-
Himanshu1khatri's post gave me this idea.
While filling, water breaches the meniscus that forms about the mouth of the clam-bottle. It is a tough little piece of surface-tension that quickly re-forms itself.
The water exits through the same diametre mouth, but more quickly.
I think that what governs the water's exit is the meniscus formed on the inside. The emptying maniscus is just as tough as the filling maniscus, but it is now the size of the inner bottle's cross-sectional area. Being larger in area means that it is not so quick to re-form itself. Water exits more quickly.
Four of five "Glugs" and the bottle is empty. The end of each 'Glug" represents the re-forming of the inner meniscus.
Mike
-
Excellent Info ROBERT.many thanks..
and Jysk (Mike) ....I am impressed !!...this young lad has some excellent ideas.
Men are the same as women, just inside out !
-
quote:
Originally posted by ROBERT
Vortices & turbulence may explain your observation.
Here is an aerodynamic analogy:-
" Vortices last longer in calm air, and atmospheric turbulence hastens their decay. Decay is the dying out of eddies. All aircraft produce wake vortices—much like two small horizontal tornadoes trailing behind the wing tips. The larger and heavier the plane is, the stronger the wake. That means small aircraft that follow larger ones can encounter turbulence if they are not kept far enough apart. The turbulence can be severe enough to cause a plane to crash. "
http://media.nasaexplores.com/lessons/01-071/5-8_1.pdf
The water in your "filling" bottle was more turbulent than when "emptying".
Right Click. Save as.
Thanks
Steven
_______________________________________________________________
In a time of universal deceit - telling the truth is a revolutionary act.