Pressure Calculations at Points A and B using Pascal's Paradox

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The discussion focuses on calculating pressures at points A and B using Pascal's Paradox, specifically in the context of gage pressure, which ignores atmospheric pressure. The user has established that the pressure at point A is zero but is struggling to determine the pressure at point B. Assumptions about the system include equilibrium, a full oil pipe, and equal surface areas in the tanks. Participants suggest equating the weights of oil and atmospheric pressure to solve for pressure at point B, while questioning the relevance of Pascal's Paradox given the differing fluid levels. The conversation emphasizes the need for clarity on assumptions and the application of hydrostatic principles.
Brownie
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Homework Statement


The points of interest are at point A and B, I want to calculate the pressures at that point. I am working in gage pressure so we can ignore atmospheric pressure.

Homework Equations


P = pgh
P = sg x specific weight of water x height

The Attempt at a Solution


Attempting a first because I am stuck at a.
I used Pascal paradox. The level I am using is at the level of the open tank oil level. Left side is p1 and right is p2.

Pressure at point 1 is = 0 (as I’m working in gage pressure)

I’m stuck at point 2.

I think I would need a to solve b
 

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Brownie said:

Homework Statement


The points of interest are at point A and B, I want to calculate the pressures at that point. I am working in gage pressure so we can ignore atmospheric pressure.

Homework Equations


P = pgh
P = sg x specific weight of water x height

The Attempt at a Solution


Attempting a first because I am stuck at a.
I used Pascal paradox. The level I am using is at the level of the open tank oil level. Left side is p1 and right is p2.

Pressure at point 1 is = 0 (as I’m working in gage pressure)

I’m stuck at point 2.

I think I would need a to solve b
You have left out a lot here, so I am going to make some assumptions:
1) The system is in equilibrium
2) The pipe is full of oil
3) The surface area in the two tanks is the same

Please let me know if those assumptions are not correct. I am not sure how you plan to use the hydrostatic paradox here because the levels in the two tanks are not equal. Let's talk about the pressure at point B. If we assume that the two tanks have the same area, then you can equate the weight of the oil in the tank on the left plus the weight of the entire atmosphere above it with the weight of the oil and air in the tank on the right. You should be able to solve for the pressure at point B.
 

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