Relative density

Relative density, or specific gravity, is the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity usually means relative density with respect to water. The term 'relative density' is often preferred in scientific usage. It is defined as a ratio of density of particular substance with that of water. Relative density, or specific gravity, is the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity usually means relative density with respect to water. The term 'relative density' is often preferred in scientific usage. It is defined as a ratio of density of particular substance with that of water.