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Q & A: Water pressure under water.

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Most recent answer: 07/08/2015
I have a 1 sq in cylinder that is filled 1000 feet underwater. What appx. force is needed to remove a piston from the cylinder at this depth if all ports in the cylinder are closed off.
- Pete Aston (age 57)
Houston, Texas, USA

Hello Pete,

The basic physics argument is that theextra pressure P of a liquid at any depth is equal to the density times the height h of the liquid and the total force on a surface is just the pressure times the area of the surface A.    There is a handy-dandy pressure calculator at


(published on 07/08/2015)

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