Very simple question - is pressure 1m down in water.

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The discussion revolves around calculating pressure at a depth of 1 meter in water. The correct formula to use is P2 = P1 + pgh, where P1 is atmospheric pressure (101.3 kPa) and pgh accounts for the water pressure (1000 kg/m³ * 9.81 m/s² * 1 m). There is some confusion regarding the use of the letter "p" for both pressure and density, but it is clarified that "small p" refers to density (rho). The total pressure at this depth is approximately 11% greater than atmospheric pressure, highlighting the significant impact of fluid pressure. Understanding these calculations is essential for accurate assessments of pressure in fluids.
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Very simple question - is pressure 1m down in water...

is it pgh?? (1000*9.81*1)...

or is it P2 = P1 + pgh.. that is.. (101.3kPa) + (1000*9.81*1)


im so confused :/
 
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Yes.I'm confused,too,because you used the letter "p" both for pressure (good thing) and for mass volumic density (bad thing)...

Daniel.
 
the small p is rho

and i figured it out :)
its the 2nd eqn
 
Of course,that's the total pressure acting on a body immersed in a fluid.However,you might have noticed it's ~11/10 times larger than the one due to air at Earth's surface,which means a difference of ~0.1 atm due to fluid pressure...

Daniel.
 

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