How Does Pressure Affect Seawater Density at Depth?

AI Thread Summary
Pressure at a depth of 5000 meters in the ocean is calculated using the formula pTotal = p_0 + rho*g*h, resulting in a total pressure of 5.06×10^7 Pa. The fractional volume change of seawater at this pressure is determined to be -2.53×10^-2, indicating a decrease in volume due to pressure. The discussion highlights confusion regarding the density of seawater at this depth, with a common assumption that density remains constant at 1,030 kg/m^3. However, the concept of bulk modulus suggests that as volume decreases, density increases, leading to a higher density at greater depths. Understanding the relationship between pressure, volume change, and density is crucial for accurately determining seawater density at depth.
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Homework Statement




Part A
What is the pressure at a depth of 5000 in the ocean? Given rho_water=1,030 kg/m^3
pTotal=p_0 + rho*g*h=5.06×107


Part B
What is the fractional volume change of seawater at this pressure? Given B=0.2*10^10
dV/v=p/-B =−2.53×10−2



Part C
What is the density of seawater at this pressure? (This is the question that I don't understand)



Homework Equations



(1)pTotal=p_0 + rho*g*h
(2)dV/v=p/-B
(3)p=F/A

The Attempt at a Solution


Part C: The liquid is incompressible. So. I guessed that the density of the liquid is still 1,030 kg/m^3 at a depth of 5,000m. And, I don't know why my answer was considered wrong.
 
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You determined the volume change from the bulk modulus.

But what is density? weight/volume?

So what was occupying a m³ is now occupying less volume
... so isn't the density now greater since you can now squeeze more into a m³?
 
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