Hello!
A barometer is used for measuring pressure, in our case the atmospheric pressure. This is achieved by balancing atmospheric pressure with the pressure of a liquid column.
The pressure of a liquid column depends only on its height, where
is the density of a liquid,
is the height of a column and
is the gravity acceleration. Mercury is often used for this purpose because of its high density (about
) which results in a relatively low height.
The times greater height of an unknown liquid means that its density is
times less than that of mercury. It is about
This isn't the density of pure water but close to it; sea water has approximately such a density.
No comments:
Post a Comment