Atmospheric pressure is measured by a device
called a barometer. A tube about 1 metre
long, with mercury in it, standing in a dish which also contains
mercury, is capable of measuring pressure: the height of the mercury
tells us the pressure in mm Hg. 1013 millibars are equivalent to 760 mm
Hg
and 1 atmosphere of pressure. In the following visual you can vary the
atmospheric pressure as you like. |
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