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Finless: You couldn't invent him...
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I am under the impression that water does not compress under pressure.

If true (not even the tiniest bit?), is it true of all fluids?

Over to you, professors.  
 

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Well, technically, it isn't true - it can be compressed eversoslightly. But for all practical purproses, it doesn't compress at all.
 

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Finless

Pedantically speaking, to scientists and engineers a fluid is a liquid or a gas, so the answer to your question is that fluids can be compressed.  Although there is a pedantic answer that'll pick holes in that too!!

Lou
 

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Just not enough dive time.
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Finless,
er how do you reckon your hydraulic brakes work?
because for all practical purposes liquids (ok Lou?) dont compress. Come to that your compass would have a hard time at depth as it too is liquid filled.

HTH
Matt
 

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Finless: You couldn't invent him...
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[b said:
Quote[/b] (MATTBIN @ Sep. 18 2003,12:56)]Finless,
er how do you reckon your hydraulic brakes work?
because for all practical purposes liquids (ok Lou?) dont compress. Come to that your compass would have a hard time at depth as it too is liquid filled.

HTH
Matt
They don't use water in h/brakes.  


Anyway, I don't care by how small an amount, water does compress under pressure.

It all makes sense now. It explains why you only want to have a pee after you start ascending during a dive.
 

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Nah - that's cos the water you've secreted into your bladder has Nitrogen in it, and when you ascend, it off-gasses and causes a pressure increase
 

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Just not enough dive time.
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Finless you doughnut you asked about other fluids/liquids so I highlighted one other non-compressable fluid as an example.
Lets get really pedantic shall we  


Dom, is that right or you winding us up? So would a good fart get rid of it or are there other risks associated with that too?

Matt
 

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[b said:
Quote[/b] (Finless @ Sep. 18 2003,10:56)]I am under the impression that water does not compress under pressure.

If true (not even the tiniest bit?), is it true of all fluids?

Over to you, professors.  
The answer is yes, You can compress water, or almost any material. However, it requires a great deal of pressure to accomplish a little compression. For that reason, liquids and solids are sometimes referred to as being incompressible.

To understand what happens, remember that all matter is composed of a collection of atoms. Even though matter seems to be very solid, in actuality, the atoms are relative far apart, and matter is mostly empty space. However, due to the forces between the molecules, they strongly resist being pressed closer together, but they can be. You probably have experienced compressing something as hard as steel. Have you ever bounced a steel ball bearing off a sidewalk? When you do that, the 'bounce' is due to compressing the steel ball, just a tiny little spot that comes into contact with the sidewalk. It compresses and then springs back, causing the bounce.

The water at the bottom of the ocean is compressed by the weight of the water above it all the way to the surface, and is more dense than the water at the surface.

A consequence of compressing a fluid is that the viscosity, that is the resistance of the fluid to flow, also increases as the density increases. This is because the atoms are forced closer together, and thus cannot slip by each other as easily as they can when the fluid is at atmospheric pressure.

professor Maniac  
 
 

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<font color='#FF7F00'>Bloody hell, all my years of working underwater ........ NOW i know what keeps wrecks in the sea bed ,,,,

the WEIGHT of water holding them down


 

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Shipwrecked & Comatose, drinking fresh mango juice
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<font color='#810541'>
[b said:
Quote[/b] ]A consequence of compressing a fluid is that the viscosity, that is the resistance of the fluid to flow, also increases as the density increases. This is because the atoms are forced closer together, and thus cannot slip by each other as easily as they can when the fluid is at atmospheric pressure.
hasn't this been discussed once before?  I seem to recall a discussion on here saying that early physicists believed that the density of water would increase with depth, so that ships that sank would reach a point below which they could sink no more.  They must have imagined ships (and cannonballs?) suspended perfectly in the depths, presumably beyond which was 'solid water'?
 

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[b said:
Quote[/b] (Andy the Commie 2 @ Sep. 18 2003,14:27)]Bloody hell, all my years of working underwater ........ NOW i know what keeps wrecks in the sea bed ,,,,

the WEIGHT of water holding them down


NO, there isn't enough weight of water to hold them up.  
 

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Finless: You couldn't invent him...
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[b said:
Quote[/b] ]Finless you doughnut you asked about other fluids/liquids so I highlighted one other non-compressable fluid as an example.
Sigh, no one understands me.  



[b said:
Quote[/b] ]Lets get really pedantic shall we  
Yes. Compressed is compressed . Even if it is only an incy wincy little bit compressed.



[b said:
Quote[/b] ]Dom, is that right or you winding us up? So would a good fart get rid of it or are there other risks associated with that too? :
I've never heard of a "willy fart".




 

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[b said:
Quote[/b] (Andy the Commie 2 @ Sep. 18 2003,14:27)]Bloody hell, all my years of working underwater ........ NOW i know what keeps wrecks in the sea bed ,,,,

the WEIGHT of water holding them down


I think what keeps the ships under water is the large hole in the side  
 

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Finless: You couldn't invent him...
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[b said:
Quote[/b] (aclivity @ Sep. 18 2003,14:33)]They must have imagined ships (and cannonballs?) suspended perfectly in the depths, presumably beyond which was 'solid water'?
Wouldn't that be COOL.  
 

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AFAIU: Fluid is a state in the middle of Liquid and Gas. Fluid will compress, though not as easy as Gas, and easier than liquid.
 This is the reason why the Van Der Vall(spell?) principle occurs in 300bar cylinders. The Gas becomes so dense it starts acting more like a fluid and thus does not compress as easily. It also decompresses a lot easier that's why you go through the first 50 or so Bar in a 300Bar tin quicker.

I'll try and find the explanation again,
Peter
 

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Finless: You couldn't invent him...
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[b said:
Quote[/b] (MATTBIN @ Sep. 18 2003,14:55)]
[b said:
Quote[/b] ]I've never heard of a "willy fart".
I cant resist but I should, it is Friday afternoon after all, how about a fanny fart?
I've heard of, and heard a FF. Never a willy fart though. I suppose it's possible. I mean I've only ever really been close to mine. Spitting, now that is another matter.

It is Thursday isn't it - anxiously looks round at the calender.
 

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Just not enough dive time.
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Well that depends on your definition of days, see I've got tomorrow off and I'm going diving up at the Farnes so in my parallel universe my brain thinks its Friday cos I'm not going to be in work whilst you lot are  

Still at least you wont have to put up with my drivel on here.
 

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[b said:
Quote[/b] (MATTBIN @ Sep. 18 2003,14:55)]
[b said:
Quote[/b] ]I've never heard of a "willy fart".
I cant resist but I should, it is Friday afternoon after all, how about a fanny fart?
Glad you did not post this on Divernet Matt, you would have been accused of toilet humour
 
 
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