(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Please help me understand when I should use [itex]\rho[/itex]gh vs. [itex]\rho[/itex]gy.

2. Relevant equations

P = [itex]\rho[/itex]gy

P =[itex]\rho[/itex]gh

3. The attempt at a solution

(In a uniformly dense solution)

[itex]\rho[/itex]gh is essentially the gravitational potential energy at a specified point in a fluid column. So "h" is taken from the bottom of the fluid to thatspecified point. It seems like this version of pressure isn'treallypressure at all because pressure is dependent on the density (and thus mass) of a fluid.

[itex]\rho[/itex]gy is an actual measure of pressure because it takes into account the mass (and thus the density) of all the fluid above some arbitrary point in the fluid.

Is my understanding correct?

...BTW I don't know calculus...

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# Homework Help: Pressure: pgh vs. pgy Please help me distinguish between the two.

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