# Mechanics

##### Article

July 5, 2022

Mechanics (Greek: Μέχανική) is one of the main branches of physics. The branch of physics that examines the effect of forces on physical bodies (regardless of whether the effect of these forces causes displacement or not), but the topic also includes the effect of forces and (if this occurs) the displacement of the body on the environment includes The roots of the discipline can be found in many ancient civilizations. The foundations of mechanics were first laid in their theories and theorems by the scientists of the early modern age, Galileo, Kepler and Newton as a whole system. All of these are now called classical mechanics. The study of mechanics is summarized in the following table:

## Classical mechanics and quantum mechanics

The two main branches of mechanics are therefore classical mechanics and quantum mechanics. Although these are discussed separately based on their differences between their fields of application, classical mechanics can also be considered a special case of quantum mechanics. Although the observations of scientific researchers who lived before his time influenced his work, Isaac Newton, the English polymath and former president of the English Royal Society, is considered the creator of classical mechanics. He formulated it by formulating three laws (more precisely, axioms) concerning the movement of matter, which he published in his three-volume book Principia Mathematica, published in 1687. Classical mechanics describes well the movement of macroscopic physical objects under the influence of forces acting on them, but only quantum mechanics, developed at the beginning of the last century, can describe the behavior of atoms and subatomic particles smaller than molecules of matter under the influence of forces. At the same time, the complexity of this relationship with quantum mechanics makes it practically impossible to deal with the macroscopic world, and the theorems of classical mechanics are used for this work. The discipline of classical mechanics is often regarded as an example of the so-called exact science, which is characterized by establishing its theorems and theories with (experimental) observation and describing them with algebraic formulas and proving the correctness of the observation.

## Newton and Einstein

Similar to the extension of the scope of classical mechanics to the behavior of the submolecular world, Einstein's general and special theory of relativity is essentially a fundamental refinement and extension of the classical theory of classical mechanics defined in Newton's theorems, already seen by Galileo, to the submolecular world and conditions in which the particle speed approaches the (impassable) speed of light . In summary: classical or Newtonian mechanics deals with the description of the motion of macroscopic bodies and the laws that apply to them; the subject of quantum mechanics, on the other hand, is traditionally the theory of the physics of elementary particles.

## Physical interpretation of the body

The term body in physics can refer to many different objects: a projectile, a spaceship, a star, mechanical units or parts, parts of solid matter, liquids or their particles, gas, etc. The other various branches of mechanics concern the appearance of bodies. Particles, for example, are parts of matter whose internal structure is still incomplete. These are considered points by classical mechanics. Rigid bodies with shape and extension are treated by classical mechanics in a similar way to particles, although even more properties can be attributed to them, as well as degrees of freedom used in certain subfields of chemistry and physics, such as their spatial orientation. Otherwise, bodies can be rigid, flexible (elastic) or liquid (fol