Could a thing contain more than its volume can w/o overflowing?

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Discussion Overview

The discussion revolves around the theoretical possibility of adding more water to a full tank through a very small hole, specifically considering the implications of water's incompressibility and the behavior of the tank under pressure. Participants explore various scenarios and physical principles related to pressure, volume, and the structural integrity of containers.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant questions whether water can remain in a full tank if more is added through a nanometer hole, suggesting a theoretical scenario.
  • Another participant asserts that if the tank is sealed, no more water can be added without overflowing, while an unsealed tank would overflow.
  • Some participants propose that the tank could bulge or burst under pressure, or that water could be compressed under extreme conditions.
  • One participant introduces the idea of a compression wave entering the hole, which could theoretically be contained if the hole closes quickly enough, but emphasizes the impracticality of such ideal conditions.
  • A participant shares a practical experience of forcing water into a high-pressure vessel, noting that despite water's incompressibility, significant internal pressures can be achieved.
  • Another participant discusses the energy considerations when pressurizing a vessel with water versus gas, highlighting the differences in failure modes and energy release upon failure.

Areas of Agreement / Disagreement

Participants express differing views on the feasibility of adding more water to a full tank and the consequences of doing so. There is no consensus on the theoretical implications or practical applications of the scenario presented.

Contextual Notes

The discussion includes assumptions about ideal conditions, such as the strength of the tank and the behavior of water under pressure, which may not hold in real-world applications. The implications of compressibility and structural integrity are also not fully resolved.

pie
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Hey, I am new in this forum and looking forward to learn physics which I hate :)

My first question concerns possibility, in theory. Say, there is a water tank. Let us say that we made a nanometer hole. The tank is full. Then, we put even more water through that hole. But the hole has something that closes very, very fast. So,

1. Could the water still be in the tank?

2. And if yes, what is going to happen then?
 
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pie said:
Hey, I am new in this forum and looking forward to learn physics which I hate :)

My first question concerns possibility, in theory. Say, there is a water tank. Let us say that we made a nanometer hole. The tank is full. Then, we put even more water through that hole. But the hole has something that closes very, very fast. So,

1. Could the water still be in the tank?

2. And if yes, what is going to happen then?
Water is essentially incompressible, so if the tank is full, how do you propose putting more water in, regardless of the size of the hole?
 
If the tank is sealed then you won't be able to put more water into the tank than it already had. If it's not sealed then it will begin to overflow.
 
Either the tank starts to bulge out or it bursts. Or, if the tank is immensely strong, you can compress the water under extreme pressures.
 
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Khashishi said:
Either the tank starts to bulge out or it bursts. Or, if the tank is immensely strong, you can compress the water under extreme pressures.
I guess you could imagine a compression wave entering the hole, which could be closed before it has a chance to bounce back after reflection inside the tank. This would assume an infinitely strong container but real water - which is slightly compressible.
I must say, I don't like these 'immovable object and irresistible force' questions. They usually emerge from real world problems, where nothing is ideal. So it would be more fruitful to grasp the nettle and address the real world problem at the start. We often get posts about electrical circuits with short circuits and perfect batteries. The thread goes round and round in circles and gets nowhere.
Choosing where and when you can validly assume infinities and zeros in Physics requires a lot of care. (Or bitter experience)
 
I do this nearly everyday. We have a 16" naval gun shell standing on its nose. Where the fuse used to be we have inputs for a high pressure pump. I fill the "bom" with water and oceanographic research instrumentation. Then via the high pressure pump I proceed to shove more water into the already full test vessel. If I force in about an extra liter of water we get internal pressures of about 8800psi. or 6000m of water depth.
Since water is nearly incompressible, how can we push more water into the test vessel? It is composed of high strength steel (2" thick at the thin spots) which is being expanded by the high pressure water.
 
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It's interesting to consider the stored energy when you pressurise a vessel. When they pressure test gas storage cylinders, it's common to use water, pumped at a few hundred atmospheres, rather than air because there is very little energy involved in pressurising the water (pressure times volume change), compared with when you pump it full of air ( several m3 of air, to start with). If the cylinder fails the 'wet test' it will just split and vent the pressure easily, with very little 'work done'. If it fails when full of air, it's a serious bomb.
 
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