Hydrometers - Physics Demonstrations - Hydrometers | Physics Undergraduate Labs

Glycerin is non-toxic but slippery when spilled. Alcohol is flammable and should be kept away from open flames or hot surfaces. Ensure adequate ventilation if using large quantities of alcohol.

Purpose

Hydrometers float at different levels in liquids of different densities, providing a direct, quantitative application of Archimedes' Principle. Students see how the equilibrium floating position depends on fluid density and how this principle is used in practical instrumentation.

Five glass hydrometers of various sizes laid out on a surface with a ruler for scale

Figure 1:

Safety Warnings

Warning: Chemical Handling

Purpose