Pressure 150m Below Sea Surface: Calculate Now!

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To calculate the pressure 150 meters below the sea surface, the relevant formula is Pressure = density × gravity × depth. The density of seawater is given as 1.026 g/cm³, and gravity is approximated at 980 cm/s². The calculation results in a pressure of 150,822,000 g/cm², which seems inconsistent with the textbook's value of 1.51 x 10⁷ dyn/cm² (15 atm). The discrepancy raises questions about unit conversions and the definition of dynes. Clarification on the calculation and unit conversions is needed to resolve the issue.
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Homework Statement


Calculate thy pressure 150m below the surface of za sea. The density of sea water is 1.026 g/cm3.


2. Homework Equations & The attempt at a solution
The pressure will depend on how much water is above you...

F = mg
F = pVg --- since density = mass per volume
F = pAdg --- since volume = area * depth
F/A = pdg
Therefore Pressure = pdg

------conversion of units--------
9.8 m/s2 * 100 cm/1 m = 980 cm/s2
150 m = 15 000 cm
--------------------------------

P = (1.026 g/cm3) * 150 000 cm * (980 cm/s2)
P = 150 822 000 g/cm2

But my textbook says 1.51 x 107 dyn/cm2 (= 15 atm)

So is my textbook wrong, or what did I do :redface: ?
 
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Btw, what is dyn?
 
sodr2 said:
150 m = 15 000 cm
--------------------------------

P = (1.026 g/cm3) * 150 000 cm * (980 cm/s2)


http://en.wikipedia.org/wiki/Dyne

--
 
:frown:

Thanks.
 
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