Specific gravity of a fluid is the ratio of its density to the density of a well-known fluid. Compare the specific gravity of water, mercury and oil. Take S_w = specific gravity of water, S_oil = specific gravity of oil, and S_M = specific gravity of mercury.

Explanation:

Specific gravity (S):

Specific gravity is defined as the ratio of the density of the fluid to the density of the standard fluid

\(Specific\, gravity\, (S)={Density\, of\, fluid\over Density\, of\, standard\, fluid}={Specific\, weight\, of\, fluid\over Specific\, weight\, of\, standard\, fluid}\)

We know that-

The density of water (ρ) = 997 kg/m³ or 0.997 kg/lit

\(Specific\, gravity\, of\, water (S_W)={Density\, of\, water\over Density\, of\, water}={0.997\, Kg/lit\over 0.997\, Kg/lit}\)

The specific gravity of water (S_W) = 1

Also, we know that the density of mercury is 13600 kg/m³ or 13.6 kg/lit

The specific gravity of mercury (S_M) =13.6

Note:- The density of most oils is less than water because most of the oils float on the water. also, the specific gravity of oil is less than the specific gravity of water.

The specific gravity of most oil (S_Oil) is less than 1.

\(Specific\, gravity\, of\, oil\, (S_{Oil})<1\)

\(S_{M}>S_{W}>S_{Oil}\)