Density
The mass per unit volume of a substance under specified temperature and pressure conditions.
Governing formula
ρ = m / V
SI unit
kg/m³
In depth
Density is an intensive property - it depends on material composition and thermodynamic state rather than object size. It dictates whether an object will float or sink in a fluid according to Archimedes' principle.
Examples in the real world
Pure water has a density of approximately 1000 kg/m³ at 4°C, whereas iron is 7870 kg/m³ and gold is 19,300 kg/m³.