How does a barometer work?

Answer 1

There are a couple of types. By far the most common is the aneroid barometer. The heart of an aneroid barometer is a sealed can. As the surrounding pressure rises and falls, the can shrinks and expands. A mechanical linkage translates the deflection into the movement of a dial. It could also be measured with a strain gauge, with the resistance translated into pressure.

The Mercury barometer has a tube sealed at the top, full of Mercury sitting in a cup full of mercury. A vacuum forms at the top because the exterior pressure can only support a column equal to the height times the density of mercury.

Air pressure pushes on the mercury inside of the container, the mercury moves up the glass tube. The greater the air pressure the higher the mercury will rise.

Answer 2

There are a couple of types. By far the most common is the aneroid barometer. The heart of an aneroid barometer is a sealed can. As the surrounding pressure rises and falls, the can shrinks and expands. A mechanical linkage translates the deflection into the movement of a dial. It could also be measured with a strain gauge, with the resistance translated into pressure.

The mercury barometer has a tube sealed at the top, full of mercury sitting in a cup full of mercury. A vacuum forms at the top because the exterior pressure can only support a column equal to the height times the density of mercury.

Air pressure pushes on the mercury inside of the container, the mercury moves up the glass tube. The greater the air pressure the higher the mercury will rise.

Answer 3

A barometer works by measuring air pressure. Changes in air pressure can indicate changes in the weather. As air pressure decreases, it generally indicates the approach of stormy or unsettled weather, while increasing air pressure can signal clearer skies.