The word weight derives from the Latin "pensum" and this from the verb pendere means "to hang", this word mainly refers to the force or energy with which a body is brought closer to the Earth; However, "weight" is a word that has several meanings, among them it refers to the object or scale that is used to weigh something in particular, it also qualifies as weight to the objects that are used to compensate or stabilize the magnitude, measurement or be it to exert some kind of pressure on any object that you want to balance. The weight is a measure of gravitational force is one of the four fundamental interactionsthat acts on an element and is identified with the energy exerted by a body on a point of support, produced by the action of the gravitational field by the unit of mass of the body under study, is represented as g and is expressed in newtons / kilogram (N / kg) in the international system of units used in almost all countries.
Because it is a force, weight is symbolized as a vector that is a physical magnitude defined by a point in space in which said magnitude is measured, as well as a module or extension, its direction or orientation, and its sense where the origin of the end applying in the center of gravity of the body and directed approximately towards the center of the earth.
The volume of the weight of an element, from the operational definition of weight, only of the power of the local gravitational field. But the mass of the body is a measure of the amount of matter that a body possesses, in a strict sense. But from a legal and practical point of view that weight is established, when the observation system is the earth that is represented not only by the local gravitational force, but also by the local centrifugal force, which is what appears when the displacement of a body in a rotating reference frame or equivalent to the artificial force perceived by a non-inertial observer.
