I saw this video on YT shorts where the guy demonstrates how it is impossible to suck water beyond 34 feet from the level it is stored at.
[This is the YT short](https://youtube.com/shorts/rWij9gJWcTg?si=5nTRvPUVFUKSaJmH)
On Google it says that the atmospheric pressure equals the pressure exerted by water column.
I don’t understand how that matters! Because in the end the guy attached a vacuum pump to pull the water up.
Also, if the water boils then it should also make steam.
Does PV=nRT apply there? I know it’s not ideal gas but for all practical purposes we use this equation.
In: Physics
Ignoring the boiling part for a moment, you can only suck water up a tube because air pressure is pushing it into the tube from the outside. The maximum distance is when the weight of the water in the tube equals the weight of a column of air outside the tube, with the same cross section, all the way up to space.
As for the boiling part, take a look at a phase diagram for water. As you decrease pressure, the boiling point drops. Below a pressure of around 611 pascals water only exists as either a solid or a vapor. So if you put a vacuum pump on it, and keep it running, the water will boil, losing heat until it freezes.
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