Understanding Pressure in Liquids

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    Liquids Pressure
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Discussion Overview

The discussion revolves around understanding how pressure changes in liquids, particularly in the context of a small tube submerged in a larger beaker of water. Participants explore the implications of air pressure and liquid pressure at different points in the system.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant questions the pressure at two specific marks in the system, suggesting that the pressure at the yellow mark should equal the air pressure inside the small tube to maintain equilibrium.
  • Another participant raises a question about the mechanism behind the water rising in the tube, proposing that it could be due to the tube being sealed or possibly due to capillary action if the tube is open at the top.
  • A different participant interprets the scenario where the water level in the beaker remains constant, leading to a discussion about whether the pressure at the yellow mark is equal to the air pressure in the tube or if it includes additional pressure from the liquid water.
  • There is a suggestion that the pressure at the pink mark could be calculated as either the air pressure in the tube plus the liquid pressure or just the atmospheric pressure plus the liquid pressure, with one participant leaning towards the first option.

Areas of Agreement / Disagreement

Participants express differing views on the mechanisms behind the pressure changes and the conditions affecting the water levels in the tube and beaker. No consensus is reached regarding the correct interpretation of the pressures at the specified marks.

Contextual Notes

Participants do not clarify certain assumptions, such as whether the tube is sealed or open, which affects the pressure dynamics discussed. There is also ambiguity regarding the definitions of pressure at the different marks.

hms.tech
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I can't seem to get a clear picture of how the pressure changes in liquids.

Here is a small self made file, made to make myself understand this topic .



Click on the attachment.

Obviously as the water rose up, air pressure in the small tube rose up. (Due to Boyle's Law)

Now let's assume (for the sake of better understanding) that i pushed the small tube half a meter inside the large beaker.

Now what is the pressure on the yellow mark ?
Is it equal to the air pressure inside the small tube, because that only makes sense. If they were not equal then there would be no Equilibrium and the water would continue to rise up/down.

And, what is the pressure at the pink mark ?
Is it :

Pressure = Desnsity x g x h + atm
= 1000*9.8*0.5 +1atm


Is the pressure on both marks the same ?
 

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Why did the water rise up the tube? I can't see a reason for that unless the tube is sealed at the top and the air in it was cooled between 1 and 2?

The only other way would be if the tube was open at the top and capillary action caused the water to rise a little way up the tube?
 
So what u are suggesting is that the water level in the beaker remains constant, thus the awter in the small tube will not rise ?

If that is the case, then the pressure at the yellow spot must be the same as the pressure of the air in the small tube, while Pressure at the pink mark will be ?

1.Air pressure in the small tube(which is higher than 1atm) plus the pressure due to liquid water
OR
2.Air pressure (1 atm) plus the pressure due to liquid water

I think it would be 1.

Am i correct ?
 
Bump

Is there no one who can help me ? :(
 

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