Definition of Specific Weight

By dividing the weight of a body by its volume we obtain the specific weight, which is expressed in newtons per cubic meter. The relationship between the weight of a body and its volume is important for decide how light or heavy different materials are.

In the language Mathematically, specific gravity is a vector quantity, since it includes an equally vector factor, the effect of gravity. The action of gravity subjected to a Unit volume in a body determines its specific weight. It is very useful in all types of sectors, especially in those in which it is important to specify the ideal conditions to process a substance.

It is also used in the engineering mechanical, in the branch of fluids or in the field of soils.

Density and specific weight

The density of an object or substance is obtained by dividing the mass by a unit of volume, which is expressed in kilograms per cubic meter. The density of a body determines its behavior in the aquatic environment, as stated in the principle of Archimedes (a body immersed in a fluid experiences an upward thrust that is equal to the weight of the fluid that evicts). According to this principle, bodies that are floating have a lower density than has the liquid, while the submerging bodies have a density greater than that of the liquid.

The density of a body expresses the relationship between the mass of a body and the volume it occupies. As a general criterion, the density of a substance is variable, as it depends on changes in pressure and temperature.

Specific gravity and density are related, since both concepts share the variable of the volume of a body. In other words, the specific gravity is equal to the density multiplied by the action of gravity.

In a figurative sense

The language of physics and chemistry is sometimes extrapolated to ordinary language. It is worth remembering that the concepts of force, mass, pressure or acceleration have a mathematical definition and, at the same time, a certain use in the communication everyday.

In this way, if an individual exerts a great influence in an organization or in a group of friends, it can be said of him that he has a great specific weight. Likewise, certain data or arguments are so important that when it comes to highlighting their relevance, they talk about their specific weight.

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