if there is a 5 inch inside dia pipe in front of you. and it is 28 ft tall. [...] it has a pressure guage on the bottom cap of the 28 ft tall pipe. it will read apx 28 ft x .433 psi = 12.124 psi when filled with water. [...]
if you place a vacuum on that air at the top[...] , what would happen to the guage pressure at the bottom of the pipe.
The pressure at the bottom of the pipe is the result of the air pressure at the top PLUS the weight of the water.
If you remove the air at the top (get a vacuum) the pressure at the bottom will be reduced (exactly by one atmosphere).
But the weight of the water doesn't change, the weight of the water is still exerting pressure at the bottom.
You can double, triple or multiply the amount of vaccum at the top - it won't change a thing.
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But as long as the weight of the water exerts less force then the pressure of 1 atm, it would be possible to open the bottom of the pipe, presse a cardboard against it, and the air pressure would hold the cardboard and the water column in place. If the water column is higher then 10.3 m the weight of the water will exert more pressure then 1 atm and this becomes impossible.
Regardless of the amount of vacuum at the top.
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Please consider again a vacuum chamber with a piston.
1 vacuum on each side, one bigger (in volume) one smaler.
Why do you think the piston should move?
There is nothing on either side pressing against it!
The piston doesn't care if there is 1 mm³ of vaccum on the left side and 100 km³ of vacuum on the right side.
How should it even know?
In a more mechanical concept pressure of a gas is the result of the average inelastic collisions of the molecules in thermal motion.
If you remove some of the molecules these collisions happen less often, hence the pressure (the outward force produced by collisions) is reduced.
If you remove all molecules, you get no collisions, ergo no pressure. But still nothing is exerting a "suction" of any kind.
Or maybe consider this:
you have a chamber divided by a piston (a closed system).
On one side of the piston the chamber is filled with a gas at 1 atm. on the other side as well.
Now remove half of the gas on the left side.
In your opinion the left side now has a "half vacuum" (ok for me) resulting in a suction force (wrong).
The piston is pressed to the left side, because the over pressure on the right side, not sucked by the low pressure on the left.
If we now move this chamber into space and open the right side to the vacuum of space (trillions of cubic light years of vacuum), the piston will be pressed outwards (by 0.5 atm pressure).
So in your world the "half vaccum" at the left is at the same time producing a "suction force" AND applying pressure.
Impossible. How should the gas in the isolated chamber know of the changed conditions in the other chamber?.
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Sorry, somehow I got carried away...
