system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: If you were to raise a large column of water from the ocean in a top-sealed cylinder with an open bottom in the water (say 300m high), would the water pressure at the bottom of the cylinder be equivalent of a depth of 300m?
gpt
You wouldn't be able to keep the water in the cylinder when you raised it. Atmospheric pressure would start pulling a vacuum in the cylinder at about 30 feet, so you would end up with 30 feet of water in your cylinder and the rest empty (or realistically full of water vapor, as the water would be boiling).