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How is vacuum measured?

  1. Feb 18, 2009 #1
    just wondering how vacuum is measured in Hg say is i had a 1L bottle and was to suck half the air out how much Hg would that be?

    cheers :)
  2. jcsd
  3. Feb 18, 2009 #2
    wouldn't it be just Pressure/2 ?
  4. Feb 18, 2009 #3


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    Staff: Mentor

    See the Wikipedia articles on the Torr (a.k.a. "mm Hg") and the barometer (paying particular attention to the "mercury barometer."
  5. Feb 18, 2009 #4
    Pressure is measured in Atmospheres or Torres. At sea level on Earth you should experience 1 Atmosphere. An Atmosphere is 760 torres so you cut that in half and you'd have a .5 Atmospheres or 380 torres
  6. Feb 19, 2009 #5
    HI to measure vacuum in hg..that inches of mercury ..thats an old method using a mercury manometer. the simplest andswer is half atmosheric pressure 1000mbar divided by two.
    Last edited by a moderator: Feb 19, 2009
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