A liquid in a container exerts pressure because of its weight.
For example, if you try to put your finger over the end of a tap when it is turned on, you can feel the pressure of the water in the pipe.
If a fluid (liquid or gas) has a density ρ, its pressure P, at a point due to the fluid of height h, is given by
where g = gravitational acceleration
Therefore, for a given liquid, its pressure:
i. increases with depth
ii. increases with density
For a given point in the fluid, its pressure acts equally in all directions.
It does not depend on the shape of containers, only on its depth.
If the density of sea water is 1150 kgm-3, calculate the pressure below 40m of sea water due to the water alone.
1 week ago