Pressure Measurement Problem

  1. Blaise Pascal duplicated Torricelli's barometer using a red Bordeaux win, of density 984 kg/m^3, as the working liquid. What was the height of the wine column for normal atmospheric pressure? Would you expect the vacuum above the column to be as good as for mercury?
     
  2. jcsd
  3. dextercioby

    dextercioby 12,307
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    The first question is trivial.Use Pascal's formula.

    Daniel.
     
  4. So that is P=Po+(row)(g)(h)
    P=1.013*10^5+(984kg/m^3)(9.8)(h).....is this correct?
     
  5. dextercioby

    dextercioby 12,307
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    No.It should be vacuum on top of the wine...

    Daniel.
     
  6. I don't understand what you are saying.
     
  7. dextercioby

    dextercioby 12,307
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    I'm saying that the experiment should be the same as in the case of Torricelli,but the length of the tube be >14 times bigger.

    Daniel.
     
  8. Gokul43201

    Gokul43201 11,141
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    What is P in this equation ?
     
  9. P is suppose to be the pressure, but im not sure what that is...I don't get this problem at all.
     
  10. Gokul43201

    Gokul43201 11,141
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    There is no other P involved.

    On one side of the column, you have atmospheric pressure (Po). On the other side, you have vacuum (P=0). So, the force due to the liquid column must balance the force due to the atmosphere.
     
  11. So is the answer -10.5?
     
  12. dextercioby

    dextercioby 12,307
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    It should be a plus.But yeah,it's good.

    Daniel.
     
  13. Is it good for mercury?
     
  14. dextercioby

    dextercioby 12,307
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    What?That #?Nope,it's computed for wine.

    Daniel.
     
  15. thanks for your help buddy...
     
  16. Gokul43201

    Gokul43201 11,141
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    Remember, you used the density of wine, not the density of mercury.
     
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