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raaaid
07-21-2007, 07:47 AM
i take a tube with 76cm of mercury and 24cm of air i invert it and sink it in mercury

whats the pressure of air inside the top of the tube?

youll say close to 0

but how can go a volume of 24cm of air from 1 atmosphere to almost 0 if it keeps being identical volume? P*V=p*v

raaaid
07-21-2007, 07:47 AM
i take a tube with 76cm of mercury and 24cm of air i invert it and sink it in mercury

whats the pressure of air inside the top of the tube?

youll say close to 0

but how can go a volume of 24cm of air from 1 atmosphere to almost 0 if it keeps being identical volume? P*V=p*v

MEGILE
07-21-2007, 07:53 AM
Magic.

FluffyDucks2
07-21-2007, 07:54 AM
Anything is possible in RaaidWorld... http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif http://forums.ubi.com/images/smilies/10.gif

BfHeFwMe
07-21-2007, 08:20 AM
http://jschumacher.typepad.com/photos/uncategorized/dead_chicken.jpg

To get to the other side?

Capt.LoneRanger
07-21-2007, 08:30 AM
I think the answer should be 42.

WhtBoy
07-21-2007, 09:29 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
i take a tube with 76cm of mercury and 24cm of air i invert it and sink it in mercury

whats the pressure of air inside the top of the tube?

youll say close to 0

but how can go a volume of 24cm of air from 1 atmosphere to almost 0 if it keeps being identical volume? P*V=p*v </div></BLOCKQUOTE>

You are confusing gauge pressure with absolute pressure.

--Outlaw.

Stew278
07-21-2007, 09:41 AM
You could change the pressure of 24cm^3 of air from 1 atm to ~0atm by cooling it in a fixed volume container.

Why would I think the pressure at the top of the tube is nearly 0? Like Whtboy said, it'd be 0atm gauge pressure, but 1atm absolute pressure.

I just tried this using a beaker of water and test tube. Fill tube 1/2 way with water, invert the tube in a beaker of water. Water stays at 1/2 height in tube. What is the pressure of the air above the water in the tube? Pressure=0atm, I doubt it. If that were the case the water would boil.

What would happen if you took the 1m tube and filled it all the way with Hg, then inverted it into a beaker of Hg. Would the level in the tube fall to ~76cm, leaving a vacuum above the Hg in the tube?

WhtBoy
07-21-2007, 09:42 AM
Gunz is right raaaid, you have a serious problem with background information. Take this question for example. You obviously read somewhere that they are using the height of the mercury at atmospheric pressure as a zero datum point for measuring pressure CHANGE. Thus you ASSUME that they mean zero pressure in the tube. That's not what they mean.

You do this with EVERYTHING. Whether it's adiabatic combustion, hydrauliclly powered pumps, or magic spirals.

In short, you are WRONG because you either CHOSE not to learn what you should learn, or, you CHOSE to move forward with conclusions BEFORE you have learned enough.

Either way the end result is that you make yourself look really really stupid when the reality is that you mostly ignorant and only a little bit stupid (because you CHOSE to remain ignorant).

--Outlaw.

raaaid
07-21-2007, 10:13 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">What would happen if you took the 1m tube and filled it all the way with Hg, then inverted it into a beaker of Hg. Would the level in the tube fall to ~76cm, leaving a vacuum above the Hg in the tube? </div></BLOCKQUOTE>

yes the vacuum would be filled with mercury vapour at close to 0 mbar, it boiled

take the experiment you did and i did as well

to be 0 mbar on vacuum part column of water should be close to 10 m

anyway rising it just 20 cm should generate some vacuum which means the trapped air should expand but as weve both seen it doesnt, how is it?

i studied that in the vaccum part of a mercury barometer its close to 0 mbar

consider initially you have 24cm3 of air at 760mbar and you sink the mercury to reach 0 mbar on the vacuum part, first volume of air will double to 48cm3 and pressure will be 380 mbar then it will go to 96cm3 and pressure will be 190 mbar

in other words if you take a half filled container and sink it level of water inside the tube should lower because vacuum is generated so air expands

but you can check the level of water doesnt lower even a mm as you take the finger off and sink it, if its the same volume of air at same temperature it must have same pressure than initially but its not

this has me confused and as usual suspicious on classical physics

raaaid
07-21-2007, 10:53 AM
ill try to be more clear take a 20 m tube half filled with water invert it and sink it in water

there will be a column of water of 10 m

pressure at water level will be 1 atmosphere so pressure on the top of the 10 m column will be 0

how can you have 10 m3 of air at 1 atmosphere and end with the same air occupying the same volume but that switched from 1 atmosphere to 0

i think current physics predict column of water lowering but you can check it doesnt

WhtBoy
07-21-2007, 11:10 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
pressure at water level will be 1 atmosphere so pressure on the top of the 10 m column will be 0 </div></BLOCKQUOTE>

No, it won't be 0. It will be less than atmospheric, but it won't be a full vacuum. If you assume that there is no heat transfer and assume that it dropped from 20m to 10m (which it won't but it's close) then, in this case, the pressure will be half atmospheric or approximately 7.5 psi.

You are WRONG.

--Outlaw.

WhtBoy
07-21-2007, 11:12 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:

i studied that in the vaccum part of a mercury barometer its close to 0 mbar
</div></BLOCKQUOTE>

That may be the case, but they didn't get the vacuum by simply inverting the tube. To get any significant vacuum you must use a vacuum pump to pull all vapor out of the space.

You didn't read the whole story or you didn't fully understand what you were reading.

--Outlaw.

raaaid
07-21-2007, 11:42 AM
you dont get my point i dont have 20 m of water before sinking the tube

i have 10 m of water and 10 of air

when i sink it what will be the level of water?

i say it will be 10 m which i think contradicts the concept of vacuum

M_Gunz
07-21-2007, 11:52 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
i take a tube with 76cm of mercury and 24cm of air i invert it and sink it in mercury

whats the pressure of air inside the top of the tube?

youll say close to 0

but how can go a volume of 24cm of air from 1 atmosphere to almost 0 if it keeps being identical volume? P*V=p*v </div></BLOCKQUOTE>

Because if you left a fraction of that much air in the tube to get to the top then it's not
going to work anyway. You're supposed to FILL the tube with your fluid and set the bottom
in the reservoir unless you want to use a very long tube.

You get a kick out of screwing up experiments?
What's next, tilt the tube over 45 degrees?

If you drive a car into a wall does that mean that driving is inherently dangerous?
Well, for whoever would do such a thing it must be!

M_Gunz
07-21-2007, 11:53 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by FluffyDucks2:
Anything is possible in RaaidWorld... http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif http://forums.ubi.com/images/smilies/10.gif </div></BLOCKQUOTE>

Anything except doing a straight experiment.

raaaid
07-21-2007, 12:07 PM
yes but my question is what happens if you just HALF fill the tube

i cant find anything on the net and dont have any mercury nor a 20 m long tube

WhtBoy
07-21-2007, 12:09 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
you dont get my point i dont have 20 m of water before sinking the tube

i have 10 m of water and 10 of air

when i sink it what will be the level of water?

i say it will be 10 m which i think contradicts the concept of vacuum </div></BLOCKQUOTE>

You are correct, I read your post wrong, my bad.

Yes, the level of the water will still be 10m and the ABSOLUTE pressure above the water will still be 1 atmosphere. Nothing is physics says the absolute pressure will be 0. ANYTHING/ANYONE that says the ABSOLUTE pressure will be 0 is wrong.

If there is no change in the volume of the space and there is no change in the mass of the fluid occupying the volume and there is no change in temperature, then the pressure will be the same. That is what physics says and it is correct.

--Outlaw.

M_Gunz
07-21-2007, 12:18 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">What would happen if you took the 1m tube and filled it all the way with Hg, then inverted it into a beaker of Hg. Would the level in the tube fall to ~76cm, leaving a vacuum above the Hg in the tube? </div></BLOCKQUOTE>

yes the vacuum would be filled with mercury vapour at close to 0 mbar, it boiled

take the experiment you did and i did as well

to be 0 mbar on vacuum part column of water should be close to 10 m

anyway rising it just 20 cm should generate some vacuum which means the trapped air should expand but as weve both seen it doesnt, how is it?

i studied that in the vaccum part of a mercury barometer its close to 0 mbar

consider initially you have 24cm3 of air at 760mbar and you sink the mercury to reach 0 mbar on the vacuum part, first volume of air will double to 48cm3 and pressure will be 380 mbar then it will go to 96cm3 and pressure will be 190 mbar

in other words if you take a half filled container and sink it level of water inside the tube should lower because vacuum is generated so air expands

but you can check the level of water doesnt lower even a mm as you take the finger off and sink it, if its the same volume of air at same temperature it must have same pressure than initially but its not

this has me confused and as usual suspicious on classical physics </div></BLOCKQUOTE>

Be suspicious about how you think to do these things first.

You don't "take your finger" off the end of the tube until it is into the reservoir or you
will let air into the tube.

76cm Hg and 24 cm air when inverted will have air on top and Hg below. Set in the reservoir
and finger off, the Hg will pull down on the trapped air and most of the Hg will flow into
the reservoir as there won't be enough pressure difference between inside the top and outside
onto the reserve to keep full height column supported. From there you are not reading outside
pressure against near vacuum but you do have a nifty spring.

I can see you in physics class failing the course because you sabotage every lab with some
screwy changes that blow the whole lesson. Only thing you learn is how to get things wrong.

In the song "Quark, Strangeness and Charm", Hawkwind starts off with "Einstein never had a
girlfriend" which is utter bollocks but appeals greatly to those that can't handle their own
failures at science by saying those who did well are losers at romance. Einstein was married,
divorced and married another woman. Neither was assigned to him, he got them in the usual
way of dating and proposal. He had kids as well.
But losers don't bother with such details, they are only interested in their wants.

WhtBoy
07-21-2007, 12:24 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by M_Gunz:
76cm Hg and 24 cm air when inverted will have air on top and Hg below. Set in the reservoir and finger off, the Hg will pull down on the trapped air and most of the Hg will flow into the reservoir as there won't be enough pressure difference between inside the top and outside onto the reserve to keep full height column supported. </div></BLOCKQUOTE>

Atmospheric pressure is 76cm of Mercury so the level of Mercury will not drop.

--Outlaw.

raaaid
07-21-2007, 12:32 PM
i believe vacuum is a force that can produce energy and theres infinite vacuum in the universe, take this example:

i build a 200km high tower and in the top i put a huge swimming pool filled with water, itll start boiling but i do the experiment before it evaporates

pressure on surface will be 0

i have 1 m3 of air at 20 m deep, the cubic meter has a pressure of two bars

i let it float at 10 m will be 2 m3 at 1 bar at 5 m 4 m3 at 0.5 bar... 8m3 16m3 32m3 64m3 128m3

as the deepness tends to 0 buyoancy tends to infinite and all with a relativily low initial potential energy

M_Gunz
07-21-2007, 12:36 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
yes but my question is what happens if you just HALF fill the tube

i cant find anything on the net and dont have any mercury nor a 20 m long tube </div></BLOCKQUOTE>

The fluid pulls down on whatever is trapped in the top (air or vapor) and fluid drains out of
the bottom of the tube (let's say fluid is salt water and bottom of tube is in the sea on a
very calm day) -until- there pressure difference between the top of the tube and outside air
to hold what is left of the liquid up.

You can hook a 15m hose to a pump so it pulls water from below the pump. Set the hose down
into a water reservoir and aim the pump to return the water to the reservoir. Start with the
pump only 1 meter above the reservoir water surface and it pumps water though you may have to
put water into the pump to get is started and you do have to power the pump. It will pump
the water just fine.
Then raise the pump and see how high you can raise it before no more water come out of the
pump. That will be right about 9.8 meters depending on how good the pump and power for it
are, of course.

Someone demonstrates something and others do the same for CENTURIES but there are always some
that think to disprove all that came before as those who did are either stupid or liars. Only
thing proved so far is that the person trying to disprove is either the stupid or the liar
time after time.
But you keep on trying. One definition of insanity is doing what fails again and again while
expecting different results. You make another definition: doing other than what works and
thinking that proves that what works is wrong.

raaaid
07-21-2007, 12:44 PM
well i got the supposely highly educated guys on the forum to disagree

M_Gunz
07-21-2007, 12:44 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by WhtBoy:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by M_Gunz:
76cm Hg and 24 cm air when inverted will have air on top and Hg below. Set in the reservoir and finger off, the Hg will pull down on the trapped air and most of the Hg will flow into the reservoir as there won't be enough pressure difference between inside the top and outside onto the reserve to keep full height column supported. </div></BLOCKQUOTE>

Atmospheric pressure is 76cm of Mercury so the level of Mercury will not drop.

--Outlaw. </div></BLOCKQUOTE>

It will if the tube is only 1 meter long! That 24cm of air is elastic and it is only pressure
difference to air over the reservoir that keeps the column in the tube up. You want 76cm Hg
then you need almost zero at the top of the tube or in this case, 2 atm pressure outside as
the 24cm of air is at 1 atm pressure when it is 24cm. How far will that stretch going to
near zero? IMO, much more than 1 meter. The Hg will fall but not completely to zero height.

M_Gunz
07-21-2007, 12:48 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
well i got the supposely highly educated guys on the forum to disagree </div></BLOCKQUOTE>

I have no degree. Even from grade school I could have spotted your errors.

raaaid
07-21-2007, 01:03 PM
well outlaw is a mechanical engineer and he disagrees with you

and you call me stupid insane and a liar for disagreeing with people that knows

raaaid
07-21-2007, 01:07 PM
Originally posted by raaaid:
you dont get my point i dont have 20 m of water before sinking the tube

i have 10 m of water and 10 of air

when i sink it what will be the level of water?

i say it will be 10 m which i think contradicts the concept of vacuum


You are correct, I read your post wrong, my bad.

Yes, the level of the water will still be 10m and the ABSOLUTE pressure above the water will still be 1 atmosphere. Nothing is physics says the absolute pressure will be 0. ANYTHING/ANYONE that says the ABSOLUTE pressure will be 0 is wrong.

If there is no change in the volume of the space and there is no change in the mass of the fluid occupying the volume and there is no change in temperature, then the pressure will be the same. That is what physics says and it is correct.

--Outlaw.[/QUOTE]


you see he says quite opposite to you

raaaid
07-21-2007, 01:12 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">You want 76cm Hg
then you need almost zero at the top of the tube or in this case, 2 atm pressure outside </div></BLOCKQUOTE>

still wondering how can you get 2 atmospheres at fluid surface level

did atmosphere thicken?

WhtBoy
07-21-2007, 01:23 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
well outlaw is a mechanical engineer and he disagrees with you

and you call me stupid insane and a liar for disagreeing with people that knows </div></BLOCKQUOTE>

Just because I have a ME degree does not mean that I can't be wrong. I will be checking on this as soon as I kick off the load calc. I'm working on.

--Outlaw.

M_Gunz
07-21-2007, 01:23 PM
Where does it say the barometer must always be in open atmosphere?

M_Gunz
07-21-2007, 01:25 PM
It's okay for Raaid to call those that have made the science and everyone that confirms it
as wrong with same implied reasons and worse but never should the blade be sharp on both sides.

FluffyDucks2
07-21-2007, 01:29 PM
http://www.simhq.com/forum/images/graemlins/default/popcorn.gif

M_Gunz
07-21-2007, 01:38 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by WhtBoy:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
well outlaw is a mechanical engineer and he disagrees with you

and you call me stupid insane and a liar for disagreeing with people that knows </div></BLOCKQUOTE>

Just because I have a ME degree does not mean that I can't be wrong. I will be checking on this as soon as I kick off the load calc. I'm working on.

--Outlaw. </div></BLOCKQUOTE>

If we have a hypothetic 1 km tube in a hypothetic 1 km deep Hg bath and we lift the uncapped
top 24cm in 1 Std Atm and then cap it.... how high will we have to lift the tube in order for
the -air- column to become 48cm tall? I would say the top would need to be 48 + 76/2 cm high
since 1/2 atm would support 76/2 cm Hg, top would be 86cm just for that. Raise the tube to
one meter and you won't have any 76cm height of Hg in it so "not with only 1 meter tube".

Perhaps you can show the derivation, at what point raising the tube there would be 75.9cm Hg?
I can bet with a smile that raise the tube 0.99 km and the Hg column will be the full 76cm.

raaaid
07-21-2007, 04:33 PM
what you say gunz make sense totally, except for calling me stupid ,insane and liar

take a bottle with 10 cm of water and 20 cm of air

if you sink it pressure of air inside will be of 0.99 atmospheres for there being a column of 10 cm

10 m column 0 atm, 5m 0.5 atm, 1m 0.9 atm, 10cm 0.99 atm

so the air inside going from 1 atmosphere to 0.99 atm should expand 1%, P*V=p*v

so if there was 20 cm of air when you had the bottle covered with your hand when you sink it it should expand 1%, of 20 cm air should expand 2 mm, lowering the level 2mm

is this correct?

now take the bottle with 10 cm of water and 20 cm of air, cover it with your hand and keep it covered as you sink the bottle

as you uncover the bottle watch the level lower 2mm

thats what youd expect right?

do it and tell me if the level lowers 2 mm

do i deserve being called names for noticing this doesnt happen?

anyway i dont make any sure afirmation

i might be wrong and be less than 2 mm, maybe 2 mm is not enough to notice but you can be sure ill make farther testing because i like the truth and im sure if free energy was posible we would be lied

converting lead to gold and making petrol valueless seem to me that is not of interest to even consider for those who rule the world

xTHRUDx
07-21-2007, 09:54 PM
http://icanhascheezburger.files.wordpress.com/2007/06/hmmmm-i-disagrees-with-your-theories.jpg

M_Gunz
07-22-2007, 09:08 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
what you say gunz make sense totally, except for calling me stupid ,insane and liar </div></BLOCKQUOTE>

Simple reaction to words you have for people who established what you say they got wrong and
other things about why the science is accepted and supported.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">take a bottle with 10 cm of water and 20 cm of air

if you sink it pressure of air inside will be of 0.99 atmospheres for there being a column of 10 cm

10 m column 0 atm, 5m 0.5 atm, 1m 0.9 atm, 10cm 0.99 atm

so the air inside going from 1 atmosphere to 0.99 atm should expand 1%, P*V=p*v

so if there was 20 cm of air when you had the bottle covered with your hand when you sink it it should expand 1%, of 20 cm air should expand 2 mm, lowering the level 2mm

is this correct? </div></BLOCKQUOTE>

Almost because if the jar is 30 cm out of water then 20.2 of air does not leave room for 10 cm
of water required to pull air down the full 2mm. So it will be some bit less than 2mm, the
solution can be found through difference of rates which no, I'm not taking the time to do.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">now take the bottle with 10 cm of water and 20 cm of air, cover it with your hand and keep it covered as you sink the bottle </div></BLOCKQUOTE>

Sink the bottle. How deep?

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">as you uncover the bottle watch the level lower 2mm

thats what youd expect right?

do it and tell me if the level lowers 2 mm </div></BLOCKQUOTE>

Pressure under water increases by 1 atmosphere about every 9.8 meters deep you go.
So how deep do you sink the bottom of your jar?

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">do i deserve being called names for noticing this doesnt happen? </div></BLOCKQUOTE>

Does Galileo deserve what you have written of him and his work?

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">i might be wrong and be less than 2 mm, maybe 2 mm is not enough to notice but you can be sure ill make farther testing because i like the truth and im sure if free energy was posible we would be lied

converting lead to gold and making petrol valueless seem to me that is not of interest to even consider for those who rule the world </div></BLOCKQUOTE>

There you go.

And free energy... geothermal energy? Sunlight? Nuclear fission of radioactives?

If you start your glass so that 20 cm of air is in the top when the bottom edge of the air
column (= surface of water inside the jar) is exactly aligned with the surface of the water
then you have 1 atm pressure air inside IF the inside air is same temperature as outside.
If the jar traps sun heat inside then the air inside will expand so keep it shaded or do
at night or indoors.

So then you can push the jar under and the pressure of atmosphere above the outside water
PLUS the pressure of the water by depth that the water surface inside the jar is below the
outside water surface as a total will push up on the air inside the jar.

I was taking Red Cross Lifeguard course and the instructor talked about rescuing some guy
that got this bright idea that he could make a 20 foot long snorkel to swim at the bottom
of the local pond and still breathe.
Funny as H, he put the garden hose end in his mouth and the top was attached to a float,
he thought he thought of everything. He did fine near the surface too. Then he held his
breath to dive to the bottom and big surprise to him when he tried to breath through that
hose. The water around him squeezed him against the much lower pressure of air in the hose,
pressed in on his belly and forced his diaphragm up. He could blow out but not breathe in
against 1.66 atmospheres the water squeezed him at and predictable as he was warned, he
had to be rescued.

You have your jar with 20cm air and take it to where the water surface inside is 9.8 meters
down, the air column should be 10 cm high.

You know that scuba divers have to deal with the same thing in terms of pressure, the air
in the tanks is compressed and the regulator matches surrounding water pressure with equal
pressure air to the diver? Or how a submarine uses air and water in the outer hull for
bouyancy to control the depth it runs?
Those _work_ by the same rules you try and dispute. They work =precisely= measurably.
In atmosphere, cars work by the same rules and do air conditioners and refrigerators.

So maybe you prove all of those are wrong too.

Or you can spend real time starting with study of the history rather than wasting your time
if you are not stupid or crazy, in which case you would be incapable of learning.