How Vacuum is Measured: Understanding the Measurement of Vacuum in Hg Units

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Vacuum is measured in inches of mercury (Hg) using the concept of atmospheric pressure, where 1 atmosphere equals 760 torr. To determine the vacuum created by removing half the air from a 1L bottle, one would calculate half of atmospheric pressure, resulting in 0.5 atmospheres or 380 torr. The discussion references the mercury barometer as a traditional method for measuring pressure. The simplest calculation involves taking the standard atmospheric pressure of 1000 mbar and dividing it by two. Understanding these measurements is essential for accurately gauging vacuum levels.
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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 :)
 
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wouldn't it be just Pressure/2 ?
 
See the Wikipedia articles on the Torr (a.k.a. "mm Hg") and the barometer (paying particular attention to the "mercury barometer."
 
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
 
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.
 
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