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.(adsbygoogle = window.adsbygoogle || []).push({});

(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

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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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# Homework Help: Question Regarding Bulk Modulus

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