Define density and relative density. Distinguish between them.
Density: It is defined as the mass of an object divided by its volume. The SI unit of density is kilograms per cubic meter (kg/m³).
Relative density: It is a dimensionless quantity, as it is a ratio of two densities with the same units.
|Mass per unit volume of a substance||The ratio of the density of a substance to the density of a reference substance|
|Density = Mass / Volume||Relative Density = Density of substance / Density of reference substance|