The Newtonian mechanical is a branch of the Physique. Since work of Albert Einstein, it is often described as traditional mechanics.
HistoryBefore becoming a science with whole share, the Mécanique was a long time a section of the Mathématiques.
Many mathematicians contributed an often decisive share there, among them of the great names such as Euler, Cauchy, Lagrange,… Until the end of the 18th century, mechanics was the natural applicatif field of mathematics, the field in which one could try to insert the experimental facts in the rigorous framework of mathematics. Conversely, certain problems of mechanics gave birth or directed the interest of the mathematicians towards theories such as the Géométrie or the differential equations.
Historically, the Mécanique statics was the first field studied by the scientists. Antiquity until the the Middle Ages of the basic concepts such as balance , celebrates it arm of lever of Archimedes or the concept more abstracted much from force was studied. Later, the interest went towards the Dynamique , i.e. the phenomena which govern the movement of the solids, field in which Galileo, for the fall of the bodies, and Newton in its famous Philosophiae Naturalis Principia Mathematica contributed decisive shares.
However, until the end of the 18th century, mechanics separated in two branches: the Mechanical of the point on a side and the Mechanical of the fluids of the other. In the case of the mechanics of the point, the studied objects are supposed implicitly indeformable and the movement of the complete solid can then be described by the movement of one of these remarkable points: the center of gravity . It was necessary to await the current of the 19th century to see appearing the first theories of the deformable solids which were going to make it possible to join together the mechanics of the solids and the mechanics of the fluids within the same framework, that of the Mécanique of the continuous mediums.
In parallel, another formalism occurred to clarify the movement of the solids: Lagrange, initially, then Hamilton developed an approach known as analytical which took as Axiome either the balance of the forces and the Accélération but the existence of a potential energy minimal which any movement of solid obeys. One can show that this approach is rigorously equivalent to the Newtonian approach; it makes it possible however to develop a radically different formalism. The principal fields of physics having recourse to the analytical mechanics are the solid state physics and the movement of complex mechanisms such as the arms of robot.
At the beginning of the 20th century, Einstein developed its famous Theory of relativity and highlighted the insufficiencies of mechanics such as it was described by Newton. However, it proves that the latter constitutes a particular case of the theory of relativity since relatively low speeds are considered. One then defined the Newtonian mechanical , or mechanical traditional , as the field of the physics which describes the movement of the bodies at low speeds in front of that of the light (either much lower than 300 000 km/s approximately). In this field, while being simpler, it provides results very close to those of the restricted Relativité, adapted as for it to all the fields speed.
Conceptually, mechanics knew three revolutions:
- the awakening that it is the acceleration which is proportional to the force (one thought initially that it was speed);
- the awakening that the movement of planets is governed by the same phenomenon that the falls of the bodies, famous universal attraction of Newton;
- the modeling of the Gravitation either by a force, but by a deformation of space with the theory of the General relativity of Einstein.
Related articlesKinematic ~ Laws of the movement of Newton ~ Analytical mechanics ~ Mechanical of the fluids ~ Mechanical of the Mechanical point ~ of the solid ~ Relativity galiléenne and Transformations of Galileo ~ Rectilinear motion uniformly accelerated
|Random links:||1158 | Guan Hanqing | Psychic TV | List members albertains about Canada | Laurent Mariotte | MacTutor | Kirsten_Dunst|