The barometer is he instrument used to measure atmospheric pressure and also to make predictions about the weather. It should be noted that areas that experience high pressure are characterized by almost no rainfall, while on the contrary, low pressure is clear predictor of strong storms that can even include very strong winds.
While, atmospheric pressure is the pressure exerted by the air on our planet earth. Atmospheric pressure corresponds to the height of a 10 m water column. High.
To the Italian-born physicist and mathematician Evangelista Torricelli he owes the creation of the barometer in the year 1643. Undoubtedly, the discovery of atmospheric pressure was the event that catapulted this Italian scientist to fame. The first barometers were provided with a column of liquid that was enclosed in a tube while its upper part was closed. It was precisely the weight of the column where the liquid was located that compensated for the weight of the atmosphere.
The unit of measure in which barometers measure is the hectopascal, whose abbreviation in writing is hPa. The unit is composed as follows: hecto = a hundred and pascals denotes the unit of measurement of pressure.
There are different types of barometers that we will detail below, although the most popular is the mercury one.
The one of mercury It was created by Torricelli as we said in the year 1643 and consists of an 850 mm glass tube. high, closed at the top and open at the bottom. The tube is filled with mercury, inverted, and the open end will be placed in a container that also consists of mercury. When uncovering it, it will be possible to see that the mercury decreases in quantity, revealing an empty space at the top. Then it will indicate the existing pressure from its measurement in the mercury column.
Other barometers are: aneroid barometer (This type is characterized by not having mercury, as it indicates the variation in pressure due to deformation in a metal box with elastic walls), barometric altimeter (used in aviation) and fortin barometer (It has a tube that will be placed in the mercury arranged in a glass container and tubular shape).
