Water Pressure

clearly didnt do homework

>>9128692
Newtonian Fluids are incompressible. There no Newtonian fluids though.
>what is pressure
Imagine a column of water 1m tall and one 100m tall, neither is flowing water, which has more pressure? How are you keeping this pressur? The static condition just means the pipe material hasnt' burst and pressure is constant.

>>9128692
The force of pressure is just the force being applied to the water, transmitted through the water. Water is (for the most part) incompressible. If you push on the water in one end of the pipe that "push" is transmitted as force in psi/bar along all surfaces of said pipe. There is not more water filling a smaller space. If i stand on a pistion filled with water the pressure increases but the piston doesnt really move.

>>9128692
If you compress enough you can turn it into solid state m8. Question is how, by taking out heat or increasing pressure?

>>9128692

The pressure within pipes is achived by either having a pump constantly forcing it, replacing "lost" pressure or by head of water. Other than that you can use expansion vessels that use pressurised air and a rubber diaphragm of sorts.

In a sealed system with none of these elements at play you would loose very little water before pressure dropped considerably.

>>9128692
Any pressure can be placed on it, up to the ultimate breaking strength of the pipe material. It remains static because the liquid reaches its max compressibility and the pipe hasn't burst. In all cases if it's static the Q flowrate is 0.

>>9128692
> fluids are in-compressible
simple thought experiment: we know sound waves travel through a given material via compression

we can observe sound waves travel though water

ergo water is compressible

>>9128692
I always assumed the pipes themselves provided the pressure, by elastic forces. When you put more water, they expand a tiny little and want to return to their original shape.

But I guess that if that were true, then hot water would reduce water pressure, which sounds weird.

>>9128692
you are not too wrong anon.

If you had a perfect uncompressible fluid. On a fixed shape hermetic container, you couldn't store any pressure on it.

the reason why you can put ome pressure, is because liquid are SIGHTLY compressible, and so is the container in most cases.

the compresison is almost neglegible, so don't worry. the expansion and contraction due to temperature is much more important, see liquid thermometers

>>9128692
>>9128747
>>9128786
>Water is (for the most part) incompressible.
>Newtonian Fluids are incompressible.
>fluids are in-compressible

Everything is compressible.

>>9128692
>Wouldn't any container you tried to fill with more water than its available volume just explode?
This is impossible because regulations prohibit the explosion failure mode, all containers experiencing an overpressure would simply leak instead. No idea where you get this idea that pressure vessels could explode when they aren't allowed to by regulations

>>9129151
Thats why i put "(for the most part)" sure at the atomic level or under insanely retardedly high pressure fluids compress a bit. For all intents and purposes though, the amount of compression is negligible. So much so, that in physics they are said to be "incompressible"

>>9129200
but it's clearly not negligible in all cases

>>9129200
Don't make blanket statements in the first place.

>>9128692
>Did my physics lecturer lie to me and water is actually compressible to an extent

Yes. It either wasnt relevant to the lecture at hand or he didnt think you could handle the concept/math.

>>9128692
A fridge is incompressible yet if you lift it onto your foot you can still feel the pressure.

>>9129204
>>9129240
Its pretty much negligible in all cases. Its closer to being negligible in all cases than it is to not being negligible in some cases.

>>9128692
Water pressure is a lie its just air trapped on top of the head of water in any water-storing vessel, this is why water tanks don't implode when you empty their contents...

>>9129313
Because your foot IS compressible The fridge feels nothing.

>>9129370
Then why do submarines implode when they go too deep?

>>9129171
>an overpressure would simply leak instead.
Semantics. "Leak" implies nothing dramatic. But in destructive pressure testing, the word "rupture" is more appropriate. Followed by leak.

>>9129494
Because the interior of the sub is a gas, not liquid. The hull therefore has a place into which it can buckle.

>>9129509
How does sound pass through it if its not compressible?

>>9129511
Sound passes through solids as well; the levels of compression are so negligible that they may as well not be there. It's like using general relativity over Newtonian mechanics for the physics of a car crash; you simply don't need to because the error is so insignificant.

>>9129525
Solids are compressible though.

>>9128692
it's compressible, but to a first approximation it acts incompressible

Does pressure exist in zero gravity?

File: regulagulatitions.jpg (33KB, 780x440px) Image search: [Google]

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>>9129171

Holy sheet, if I had some of those regulations. I'd prohibit to be a moron.

Whadda'you think, you'd suddenly wise up, or drop dead ?

>>9129932
yes if you put a pressure vessel into the space it still has pressure

but its walls also would experience a negative pressure in all directions from the vacuum wanting to pull it apart.

>>9128692
>if fluids are in-compressible, how can water be kept under pressure?

Usually by sex or drugs. Flouride is a hell of a drug! I'm rick James bitch!

>My desk isn't compressible, how come when I bang my head on it, it doesn't explode?

Why has nobody asked this yet.


If you have a big steel casing, but completely filled with water, and you froze it, would it freeze, breaking the container? Or would it stay liquid at any temperature.

File: Phase-boundary-curves-of-water-in-a-p-T-diagram-For-a-reasonable-pressure-scale-in-this[1].gif (81KB, 700x718px) Image search: [Google]

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>>9132350
If it got cold enough it would freeze and the expansion would crack the casing. That's why people in cold climates are supposed to leave their tap running a bit if they lose heating.

>>9129375
>The fridge feels nothing
that's what she said

>>9128692
Fluids aren't incompressible. At high enough pressures everything is compressible.

Infinite gravity applied from all sides would probably compress some water.