Unformatted text preview: easily. In a water barometer, the situation is quite different. Water's vapor pressure is much greater and the pressure exerted by water vapor at the top of the barometer would have to be taken into consideration. The vapor pressure exerted is pretty much a non-factor with a mercury barometer. However, with a mercury barometer, two additional components are necessary in order to increase the accuracy of a barometer. These two components are a vernier scale and a thermometer. The vernier scale allows for greater measurement accuracy than what is possible by just reading the scale itself. The thermometer is needed because the mercury's density (in addition to the density of other materials used in the assembly of the barometer) change with temperature. Many barometers come outfitted with thermometers attached to them....
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- Summer '10
- Pressure measurement, Water vapor, 34 ft, water barometer