Problem of manometry. Is it resolved correctly?

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    Mechanic of fluids
AI Thread Summary
The discussion centers on solving a manometry problem involving a tank with specified dimensions and pressures. The user calculated the manometer reading "A" as -76.97 kPa and the height "h" of the mercury manometer as 0.124 m. There is a request for clarification on the symbols "S" and "γ," as well as a suggestion to present calculations in symbolic form before finalizing numerical values. The importance of clearly stating constants used in calculations is emphasized for better understanding. Overall, the conversation highlights the need for clarity and precision in presenting mathematical solutions.
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Homework Statement


upload_2015-3-13_14-50-34.png

The tank shown in the figure is located in a place with a
atmospheric pressure (90 kPa abs).
If X = 3.50 m, Y = 1.80 m and the vapor pressure of the alcohol is
13 kPa (abs), determine:
1) manometer reading "A" in KPa.
2) The height "h" of mercury manometer.

Homework Equations



[PLAIN]http://upload.wikimedia.org/math/3/3/4/334de1ea38b615839e4ee6b65ee1b103.png= S(fluid)*[PLAIN]http://upload.wikimedia.org/math/3/3/4/334de1ea38b615839e4ee6b65ee1b103.pngwater
[/B]

The Attempt at a Solution


I have did this:
Equating P(A) = P (alcohol) + 0.035 (Salcohol) ([PLAIN]http://upload.wikimedia.org/math/3/3/4/334de1ea38b615839e4ee6b65ee1b103.pngwater )
P(A) = -76.97 kPa. (Using P(alcohol)= Palchol abs -Patm = -77 kPa)

Equating

P(A) +[PLAIN]http://upload.wikimedia.org/math/3/3/4/334de1ea38b615839e4ee6b65ee1b103.pngalc (h) +1.8 http://upload.wikimedia.org/math/3/3/4/334de1ea38b615839e4ee6b65ee1b103.png (alc) = [PLAIN]http://upload.wikimedia.org/math/3/3/4/334de1ea38b615839e4ee6b65ee1b103.png(Hg) (h)
Solving for "h"
h=0.124 m
 
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What do "S" and "γ"? stand for?
 
The combination of showing work in numerical form instead of symbolic, yet not showing what values you areusing for constants, makes it very hard to follow. Please post your working in purely symbolic form, until the final step, and state what values you are using for g, atm, alcohol's SVP, and the densities.
 
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