What stress needs to be exerted to turn a quart of water into a pint?

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SUMMARY

The discussion centers on the physics of compressing a quart of water (946 ml) into a pint pot (473 ml) using a steel piston with a radius of 1 mm and a length of 10 m. The calculated stress required to achieve this compression is approximately 2.2 GPa, leading to a pressure of 1.1 x 109 Pa. The conversation highlights the impracticality of the scenario, noting that water is nearly incompressible and would require extreme pressure, far beyond the capabilities of conventional materials.

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Homework Statement


Dr Stewart’s Aunt Sally was constantly reminding him that he couldn’t squeeze a
quart (946 ml) into a pint pot (473 ml). Annoyed by this negative attitude, he set
about proving old Sally wrong. He constructed a platform, resting on a steel piston
radius 1 mm, length 10 m, bearing down on a chamber of equal radius, containing
1 quart of water. He then placed a number of 1000 kg elephants, procured from the
local zoo, on the platform.
What stress needs to be exerted to turn a quart of water into a pint?


Homework Equations


B=-P/(dv/v)
stress = F/A


The Attempt at a Solution



2.2Gpa(473/946)=P
=1.1*10^9

Not really sure what to do from here...
 
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Hope that the zoo has a lot of elephants available. Water is very nearly incompressible. You are looking at a 50% reduction in volume which is going to require extreme pressure, very extreme pressure!
 
OldEngr63 said:
Hope that the zoo has a lot of elephants available.
Do the math. Not even one elephant is needed. And these are small elephants.

That's assuming this piston or cylinder could exist. Both would have to be made of unobtanium.