What is the principle of the barometer and how it works?
There are several way in which a barometer work. The most common is a needle attached to a spring and a tensioning device which expands and contracts based upon the amount of atmospheric pressure it is exposed to. The second type is what is called Galileo’s barometer. Globes are filled with a number of liquids of different specific gravities (this is the density of the liquid with respect to the density of water). As the air pressure changes, these different globes will either float or sink based upon the changes in air pressure. The third type is the electronic barometer. It uses a pressure transducer, which causes changes in electric current bases upon changes in air pressure. These changes are converted into either an analog (needle meter) or digital display of the value of the air pressure.
