It is called buoyancy to ability of a body to stay within a fluid.
The buoyancy of a body within a given fluid will depend on the different forces acting on it and the direction they present. The buoyancy will be positive when the body tends to rise within the fluid, on the other hand, it will be considered negative if the body, on the contrary, tends to descend in the fluid in question. Meanwhile, it will be neutral, when the body remains suspended, in suspension, within the fluid.
Buoyancy is determined by the Archimedes' principle; This principle holds that a body totally or partially submerged in a fluid at rest, will receive a push from the bottom up that will be equal to the weight of the volume of the fluid it displaces.. The aforementioned force is known as hydrostatic or Archimedean thrust, in honor of its discoverer: Archimedes, a Greek mathematician, astronomer, inventor, engineer, and physicist who was noted for his postulations and discoveries in Ancient Greece between 287 and 212 BC.
It should be noted that if the body in question is compressible in nature, the buoyancy will be modified by varying its volume according to what is established by the law of Boyle- Mariotte. This law formulated by Robert Boyle (French chemist) and Edme Mariotte (French physicist) holds that volume is inversely proportional to pressure.
Meanwhile, the term buoyancy is closely linked to the concept of floatation of a body. A body will be in a floating state when it remains suspended in a liquid or gaseous environment, that is, in a fluid and as long as the number of particles that make up the object is less than the number of particles of the fluid displaced.
