[ELI5] Can one physically compress water, like with a cyclinder of water with a hydraulic press on the top, completely water tight, pressing down on it, and what would happen to the water?

Question

[ELI5] Can one physically compress water, like with a cyclinder of water with a hydraulic press on the top, completely water tight, pressing down on it, and what would happen to the water?

In: 1967

Answer 1

As others have said, water is considered incompressible for all practical purposes. That’s why hydraulics are so powerful. It’s why you can lift a car on a column of oil. If the liquids compressed, it wouldn’t work.

When you learn about air as a fluid, and related principles like Bernoulli, one of the first things they teach you is that gaseous fluids can generally be compressed, but liquid fluids like water cannot.

Others have explained here that this is a general principle for practical purposes, not an inviolable law. Apparently you can compress water, but not with the pressures associated with normal equipment used in hydraulics.

This is a great question. Good job, OP