Units for pressure in a cylinder

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When calculating pressure in a spherical cylinder using a manometer filled with water, the hydrostatic formula P2-P1=ρg(h2-h1) requires consistent units for accurate results. The density (ρ) is in kg/m^3, and gravity (g) is in m/s^2, so height (h) can be expressed in either meters or millimeters. If height is measured in millimeters, the resulting pressure will be in N mm/m^3, which is equivalent to mPa. For standard pressure units, it is advisable to use height in meters to maintain consistency and clarity in results. Thus, while mm can be used, it is better to stick with meters for conventional pressure calculations.
Pranshu
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I am calculating pressure on a spherical cylinder of 10 mm diameter by wind tunnel. when measuring values in manometer filled with water which density is 1000 kg/m^3 so by hydro-static formula the pressure difference is [P2-P1=ρg(h2-h1)]

so by this formula the ρ unit is in kg/m3 and gravity(g) we know 9.81 m/s^2 so the unit of (h2-h1) must be meter? or mm will be fine as well?
I am confused by this small problem..

<<Mentor note: Removed comments unrelated to question>>
 
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The formula does not presuppose anything about the units. You will get the same units out as you put in.
 
Orodruin said:
The formula does not presuppose anything about the units. You will get the same units out as you put in.
Thank you...

But the unit which i put in must be same...for instance if i have ρ in meter and g in meter as well...so can i use h means the height in mm?
or it should be meter too?

that's my real question.
 
You can use h in mm, but it will make your result have units of N mm/m^3 instead of N/m^2. (The first is equivalent to units of mPa.)
 
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