What is #"relative density"#?

1 Answer
Nov 20, 2016

The density of a material relative to that of a reference substance....

Explanation:

....And the reference substance is typically water, for which #rho=1*g*cm^-3#.

And thus iron, which has #rho=7*g*cm^-3#, has a relative density of..

#"Reltive density of iron"# #=# #(rho_"iron")/(rho_"water")=(7*g*cm^-3)/(1*g*cm^-3)=7#.

The relative density is thus a dimensionless quantity. Given its superior relative density, iron will sink in water as it displaces a volume of water whose mass is LESS than the mass of the iron.