The specific gravity of a substance is the dimensionless ratio of its density to the density of water:
$$ SG = \frac{\rho}{\rho_{H_2O}} $$
Where
- ( \small SG ) is the specific gravity,
- ( \small \rho ) is the density of the substance, and
- ( \small \rho_{H_2O} ) is the density of water.
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