Question regarding water pressure and slopes

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Discussion Overview

The discussion revolves around the effects of water pressure in different configurations of pressure sensors placed on the ocean floor, specifically comparing a sensor surrounded by slopes to one on a flat plain. Participants explore the implications of static pressure and flow rates in various scenarios involving orifices and containers.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions whether two identical pressure sensors at the same depth would read the same PSI when one is surrounded by slopes and the other is on a flat plain.
  • Several participants assert that both sensors will read the same value of pressure, referencing the principle that pressure does not depend on the shape of the container.
  • A participant expresses uncertainty about the appropriate measurement for their question, suggesting it might be head pressure.
  • Another participant notes that while static pressure is the same, the flow rate through an orifice is influenced by multiple factors beyond just pressure, indicating the complexity of fluid dynamics.
  • One participant introduces Pascal’s law in relation to the scenario involving holes and a large empty container, suggesting it could be applicable.
  • A later reply clarifies that the quantity of water exiting an orifice is better described in terms of flow rate rather than force, emphasizing the distinction between flow and force in fluid dynamics.

Areas of Agreement / Disagreement

Participants generally agree that static pressure is the same in both scenarios, but there is ongoing discussion regarding flow rates and the implications of different configurations, indicating that multiple views remain on the topic.

Contextual Notes

Participants express uncertainty about the definitions and measurements relevant to their questions, particularly regarding head pressure and flow rate, which may affect the clarity of the discussion.

Jstoff
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TL;DR
Questioning regarding water pressure PSI and slopes.
I have a question about water pressure PSI regarding the presents/lack of slopes.

If two identical pressure sensors are set up on the ocean floor at the same depth. One being surrounded by a cone of ramps increasing in height moving outwards away from it. The second sitting on a flat plain with no increase or decrease of the surrounding ocean floor. (I've attached an illustration for explain.) In this situation would the sensors read the same or different PSI? If different which one would be higher?

Sorry if this isn't the correct area to post in. Wasn't sure what this fit under honestly. Thanks for the help!
 

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Lnewqban said:
Welcome!
Both sensors will read the same value of pressure.

Please, see:
https://www.physicsforums.com/threa...-depend-on-the-shape-of-the-container.978355/
I appreciate the quick reply! Thanks for the link I believe it really cleared things up for me. It also made me relies that i forgot an important part of my question. To be honestly I'm not sure what measurement would be most appropriate for the answer of this question. I believe its head pressure but I'm not sure if I'm using it in the right context.

What if sensors 1 and 2 were replaced with twos holes of the exact same dimensions. On the other side of the hole there's a large empty container. Would the force of water coming out the other side be the same? I'm assuming they would if the static water's PSI was the same. Just i just wanted to make sure.
 
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You understand that the static pressure (with nothing moving) is always the same.
The flow rate through an orifice depends upon more things than just the pressure. Our ability to describe such situations simply is very limited although it has been the subject of intense scrutiny for as long as there has been science. Now we have powerful computing machines and it is still difficult. In previous decades and centuries various specific and extraordinarilly clever approximations in fluid dynamics have been developed.
In general a more "streamlined" (a term from said fluid dynamics) orifice will produce more flow.
 
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Jstoff said:
... What if sensors 1 and 2 were replaced with twos holes of the exact same dimensions. On the other side of the hole there's a large empty container. Would the force of water coming out the other side be the same? I'm assuming they would if the static water's PSI was the same. Just i just wanted to make sure.
I can’t visualize what you describe, but Pascal’s law could be applied to that case:

Please, see:
https://en.m.wikipedia.org/wiki/Hydrostatics
 
Jstoff said:
Would the force of water coming out the other side be the same?
It's not a force that come out, but it is quantified as flow rate, either volumetric or mass(emetric), momentum, velocity. The force comes about only when the stream contacts another surface and should not be confused with the above.
 
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