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Homework Help: Problem of manometry. Is it resolved correctly?

  1. Mar 13, 2015 #1
    1. The problem statement, all variables and given/known data
    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.

    2. Relevant equations

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

    3. 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 [Broken])
    P(A) = -76.97 kPa. (Using P(alcohol)= Palchol abs -Patm = -77 kPa)


    P(A) +[PLAIN]http://upload.wikimedia.org/math/3/3/4/334de1ea38b615839e4ee6b65ee1b103.pngalc [Broken] (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) [Broken] (h)
    Solving for "h"
    h=0.124 m
    Last edited by a moderator: May 7, 2017
  2. jcsd
  3. Mar 13, 2015 #2

    rude man

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    What do "S" and "γ"? stand for?
  4. Mar 13, 2015 #3


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    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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