Question Regarding Bulk Modulus

AI Thread Summary
The discussion revolves around calculating the change in volume of seawater when taken from the surface to the Mariana Trench, focusing on the bulk modulus of water. The user initially struggles with the calculation using the bulk modulus equation, leading to confusion over the sign of the volume change. After applying the formula, they arrive at a negative volume change, which they hesitate to submit due to potential grading issues. Ultimately, the user resolves their problem independently and indicates that further assistance is no longer needed. The conversation highlights the complexities of applying theoretical concepts to practical problems in fluid mechanics.
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The deepest point in any ocean is in the Mariana Trench, which is about 11 km deep, in the Pacific. The pressure at this depth is huge, about 1.13 X 10^8 N/m^2.

(a) Calculate the change in volume of 1 m3 of seawater carried from the surface to this deepest point.
wrong check mark m3

(b) The density of seawater at the surface is 1.03 X 10^3 kg/m3. Find its density at the bottom.
kg/m3

(c) Is it a good approximation to think of water as incompressible?
Yes
No

-----------------------------

The above is the question. Now, I didn't think I would have an issue with this, but apparently I am. The bulk modulus equation is:

B = -ΔP/ [(ΔV/Vi)] where:
B = bulk modulus, ΔP = change in pressure, ΔV = change in volume and Vi = initial volume.

I am trying to find ΔV for part A (afterwards the rest should not be difficult at all).

So ΔV = -[ΔP(Vi)]/B

When you use 0.21 X 10^10 for the bulk modulus of water (which apparently the online assignment website wants this for water and not seawater), you get:

ΔV = -(1.13 X 10^8)(1)/(0.21 X 10^10) = -0.0538 m^2

I actually inputted this into the website as a positive value and it counted it as wrong. The reason this is strange is because it will normally say "wrong sign" and if it's off by 10% or less it will say so. So I am hesitant to input in the negative value because that will be my last submission. Any help is appreciated. Thanks.
 
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This can be locked, I figured out the problem.
 
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