Density ratio between an object and a fluid
$
\text{Specific Gravity}, SG= \frac{\rho_\text{object}}{\rho_\text{water}}
$
$
\rho_\text{water}=1000\,\text{kg\,m}^{-3}
$
Object with $SG\lt1$ floats, sinks otherwise
Denotes fraction of a floating objecting submerged underwater
- an object made of a material with a specific gravity of 0.2 will have 20% of its volume underwater