Manometer -- determine height from relative pressure

Thread starter daphnelee-mh
Start date Sep 28, 2021
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Height Manometer Pressure Relative

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The discussion centers on calculating height using a manometer and relative pressure. A participant asserts that the correct height is 5.6 meters but is uncertain about their calculations. There is confusion regarding the equations used, specifically the relationship between gauge pressure and absolute pressure. One participant questions the accuracy of the initial equation presented, suggesting an alternative formulation. The conversation highlights the importance of correctly applying pressure equations in fluid mechanics.

Sep 28, 2021

daphnelee-mh

Homework Statement: A Burdon gauge is mounted on the top of the vessel at point M . The relative pressure at M is -980Pa, determine h1 if H=1.5m, h2=0.2m

Relevant Equations: Pm=Pa- Pmabs

The correct answer is 5.6m, not sure where I made the mistake.

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Sep 28, 2021

haruspex

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##P_{M gauge}=P_{atm}-P_{M abs}##?
Doesn't look right to me.

Sep 28, 2021

Chestermiller

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I get ##P_{Mabs}=p_{atm}+P_M##

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