Question Regarding Bulk Modulus

Click For Summary
SUMMARY

The discussion centers on calculating the change in volume of seawater when subjected to extreme pressure at the Mariana Trench, approximately 11 km deep. The bulk modulus of water is utilized in the calculations, specifically using a value of 0.21 X 10^10 N/m². The user successfully derived the change in volume (ΔV) as -0.0538 m² but faced issues with the online submission system, which did not accept the negative value. The user ultimately resolved the issue independently.

PREREQUISITES
  • Understanding of bulk modulus and its formula: B = -ΔP/[(ΔV/Vi)]
  • Knowledge of pressure changes in fluid mechanics
  • Basic principles of density and its relationship with pressure
  • Familiarity with the properties of seawater versus freshwater
NEXT STEPS
  • Research the implications of pressure on fluid density in oceanography
  • Learn about the bulk modulus of different fluids, including seawater
  • Explore the concept of incompressibility in fluids and its limitations
  • Investigate numerical methods for solving fluid mechanics problems
USEFUL FOR

Students and professionals in physics, oceanography, and engineering who are dealing with fluid mechanics and pressure-related calculations in deep-sea environments.

Ithryndil
Messages
142
Reaction score
0
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.
 
Physics news on Phys.org
This can be locked, I figured out the problem.
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
9K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 5 ·
Replies
5
Views
24K
Replies
3
Views
10K
Replies
6
Views
4K
  • · Replies 10 ·
Replies
10
Views
4K
  • · Replies 2 ·
Replies
2
Views
3K
Replies
5
Views
2K
Replies
3
Views
11K
  • · Replies 1 ·
Replies
1
Views
2K