Answer:
It is the pressure exerted by the Earth's atmosphere at a given point, equivalent to the pressure exerted by a column of mercury (its value is 760 mm of mercury).
Step-by-step explanation:
The weight of the air that forms our atmosphere puts pressure on the surface of the earth. This pressure is known as atmospheric pressure. Generally, the more air there is over an area, the higher the atmospheric pressure. This means that atmospheric pressure changes with altitude.
To compensate for this difference with altitude and facilitate comparison between places with different altitudes, the atmospheric pressure generally adjusts to the equivalent pressure at sea level. This pressure is known as barometric pressure.
The barometer is used to measure the barometric pressure values. This instrument was invented in 1643 by Evangelista Torricelli, who used an open tube at one of its ends to introduce mercury into its interior, verifying that the level of mercury fell to a height of 760 mm, regardless of the diameter or shape of the tube.