'

Density ( temperature dependence)

Description

The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume. The density of a material varies with temperature and pressure. In most materials, heating the bottom of a fluid results in convection of the heat from the bottom to the top, due to the decrease in the density of the heated fluid. This causes it to rise relative to more dense unheated material. In the case of volumic thermal expansion at constant pressure and small intervals of temperature the temperature dependence of density is depended on the density at a reference temperature and the change of the temperature.

Related formulas

Variables

ρThe density of the material on a change of temperature (kg/m3)
ρoThe density at a reference temperature (kg/m3)
αthe thermal expansion coefficient of the material close to To. (K-1)
ΔTThe change of temperature (K)