This property
is also used to measure the density of a liquid using an instrument called a HYDROMETER. This is a glass tube with a scale on the side
weighted at the bottom with lead shot. The hydrometer floats in the liquid and if the liquid is
dense the hydrometer does not need to sink very low to displace its own weight of liquid. If
the liquid has a lower density it will sink much deeper.
Hydrometers are used to check
the density of car battery acid, beer, milk and wine. Two types are drawn
below.
