Specific Weight

ω (sometimes γ, and sometimes known as specific gravity) is defined as the weight per unit volume or the force exerted by gravity, g, upon a unit volume of the substance. The relationship between g and ω can be determined by Newton’s second law, since weight per unit volume = Mass per unit volume × g. S.I. unit of fluid is Newton per cubic metre, N/m³, and dimension is ML^{− 2} T^{− 2}.