Specific weight

The density of a material is defined as mass divided by volume, typically expressed with the unit kg/m3. Unlike density, specific weight is not a fixed property of a material, as it depends on the value of the gravitational acceleration, which varies with location (e.g., Earth's gravity). In practice, the standard gravity (a constant) is often assumed, usually taken as . Pressure may also affect values, depending upon the bulk modulus of the material, but generally, at moderate pressures, has a less significant effect than the other factors. == Applications ==

Fluid mechanics In fluid mechanics, specific weight represents the force exerted by gravity on a unit volume of a fluid. For this reason, units are expressed as force per unit volume (e.g., N/m3 or lbf/ft3). Specific weight can be used as a characteristic property of a fluid. }} {{defn|The difference between the saturated unit weight and the unit weight of water. It is often used in the calculation of the effective stress in a soil. The formula for submerged unit weight is: \gamma' = \gamma_\text{s} - \gamma_\text{w} where • is the submerged unit weight of the material • is the saturated unit weight of the material • is the unit weight of water }} Civil and mechanical engineering Specific weight can be used in civil engineering and mechanical engineering to determine the weight of a structure designed to carry certain loads while remaining intact and remaining within limits regarding deformation. == Specific weight of water ==