How Does Water Pressure Change with Column Height and Diameter?

AI Thread Summary
Water pressure increases beneath a vertical column due to the weight of the water above it, which can be calculated using the formula P = hDg, where P is pressure, h is the height of the water column, D is the density of the water, and g is the acceleration due to gravity. The pressure at the base of the column is directly proportional to the height of the water and its density. Additionally, varying the diameter of the column does not affect the pressure at the base, as pressure is independent of the area of the column. Understanding these principles is essential for solving related physics problems. This foundational knowledge is crucial for applications in fluid mechanics and engineering.
mjp42@csufresno.edu
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Explain why pressure increaseds beneath a vertical column of water and how to calculate water pressure ate the base of the column. Include the effect of varying heights and column diameters.

thanks

mike
 
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This sounds suspiciously like a homework assignment.

It also sounds suspiciously as though you haven't even attempted it -- the answer is simple and should be easy to find in any first-year physics textbook.

- Warren
 
The pressure is based on the weight that must be supported at the given depth. The volume of a the cylinder is just area * height

v =ah

Now you find the mass of the water which is just density * volume. I don't remember the symbol for density so I'll just use D.

m = vD

m = ahD

Now add gravity

F = ahDg

Now find the pressure on the bottom of the cylinder by dividing by the area

P = hDg

There you have it, the pressure at a given depth is height * density * gravity.
 
The normal symbol for mass density is \rho :smile:

- Warren
 
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