Fluid density
Fluid density is a physical property that indicates the weight of a fluid per unit volume. Basically, it expresses how much matter is contained in a unit volume of liquid. The density of a fluid is usually denoted by the symbol ρ (rho) and is measured in units of mass per unit volume, such as kilograms per cubic meter (kg/m³) in the SI system of units.
The density of a liquid varies depending on its composition, temperature and pressure. For incompressible liquids such as water, density is the average of density values at different temperatures and pressures.
The density of liquids is an important physical property with a wide range of applications. It plays a key role in fluid volume and weight calculations, in hydraulics and hydrodynamics, in pressure and force calculations, as well as in the analysis of fluid flow in various systems and devices, including water networks, tanks, pumps, and the like.
The density of a liquid is also important in determining its buoyancy (whether the liquid will float on the surface of other liquids or sink) and in determining the concentration of substances in aqueous solutions. It also affects the properties of heat transfer and chemical reactions in fluids.