mechanics

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The mechanics (by ancient Greek μηχανικὴ τέχνη mechané , German , machine trick mode of action ' ) is in the sciences and engineering sciences , the study of the movement of bodies , as well as the thereby acting forces . In physics , mechanics is usually understood to mean classical mechanics . In the sub-area of theoretical physics , the term is often used in abbreviation for theoretical mechanics . In engineering, it is usually understood to mean technical mechanics , which uses the methods and fundamentals of classical mechanics to calculate machines or structures.

Both the theory of relativity and quantum mechanics contain classical mechanics as a special case.

The Classical Mechanics was in the 17th century mainly by the work of Isaac Newton founded and became the first science in the modern sense (see History of classical mechanics ).

Subdivision

Structuring the mechanics from the
point of view of the forces involved
 
 
 mechanics
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Kinematics Laws of
motion
without forces
 
 Dynamics
effect of
forces
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 Statics
Forces in equilibrium of
resting bodies
 
 Kinetic
forces change the state of
motion

Mechanics can be roughly subdivided into different sub-areas: Kinematics deals with the movement of bodies and primarily describes the trajectory , speed and acceleration of bodies without taking mass or forces into account. The dynamic extends the description of the movements through the mass and the acting forces . Dynamics are often divided into statics (forces in equilibrium) and kinetics (forces not in equilibrium). In technical mechanics, on the other hand, they are also divided into kinematics and kinetics and understood as a sub-area that stands alongside statics.

In addition, special sub-areas of mechanics can be divided according to many different criteria.

The division already described above according to the consideration of forces results in:

A classification according to the state of aggregation is as follows:

The classification according to area of ​​application leads to:

A classification according to the type of idealization includes:

Education

Mechanics is taught on the one hand as part of the physics course and on the other hand as part of engineering training, for example in the course of mechanical engineering or civil engineering . There are also a few special courses in mechanics, some of which are called Applied Mechanics :

Connections to related scientific disciplines

Connections to other scientific disciplines arise between classical mechanics and some scientific disciplines, as well as between technical mechanics and engineering disciplines.

Connections in the natural sciences

In biology is the biomechanics a special application of mechanics and the chemistry the reaction kinetics , which deals with kinetic energies of reactants and chemical reactions.

In the theoretical structure of physics, there are diverse connections: Hamilton mechanics is a very general formulation of classical mechanics which contains both Newtonian mechanics and quantum mechanics as special cases . Systems that consist of a large number of bodies can theoretically be described by the movements of the individual bodies. In practice, the solution of the numerous equations that are required is no longer possible from a certain number of bodies; the Statistical Mechanics then deals with statements such many-body systems . From a size of about 10 23 particles, the predictions of statistical mechanics agree very well with those of thermodynamics . The theory of relativity contains classical mechanics as a special case for small speeds.

Connections in engineering

Technical mechanics basically provides general calculation methods without going into special construction materials (only parameters such as strength and elasticity are taken into account, but not whether it is wood or steel) and does not deal with special components.

Findings from the independent engineering discipline of materials technology are integrated into strength theory , which is a field of technical mechanics.

In mechanical engineering, the field of machine elements (screws, gears, etc.) is very close to mechanics. There are special equations for calculating the necessary dimensions for the respective machine elements. The driving dynamics is both part of the dynamics and the vehicle technology . The Mechatronics is an interdisciplinary field that consists of shares of mechanics / mechanical and electrical engineering. Special areas of technical mechanics in mechanical engineering are machine dynamics and rotor dynamics . In gas turbines , fluid mechanics (aerodynamics) is so closely related to thermodynamics that it is sometimes referred to as aero-thermodynamics.

In civil engineering has a special affinity for the structural analysis of the structural civil engineering on. This takes into account the peculiarities of special building materials and is divided into timber and steel construction as well as concrete and reinforced concrete construction , while structural engineering creates and provides calculation methods that are independent of the construction method and are therefore a fundamental technical and scientific discipline. Further areas are soil mechanics , rock mechanics and subsoil dynamics .

Web links

Wikibooks: Mechanics of Liquid and Gaseous Bodies  - Learning and Teaching Materials
Wikibooks: Mechanics of Real Bodies  - Learning and Teaching Materials
Wikibooks: Mechanics of Rigid Bodies  - Learning and Teaching Materials
Wikisource: Mechanics  - Sources and full texts
Wiktionary: Mechanics  - explanations of meanings, word origins, synonyms, translations

Individual evidence

  1. ^ Heinz Dieter Motz: Engineering Mechanics: Technical Mechanics for Study and Practice . Springer-Verlag, March 8, 2013, ISBN 978-3-642-95761-1 , p. 1.
  2. ↑ Jürgen Mittelstraß: The Greek way of thinking: From the emergence of philosophy from the spirit of geometry . De Gruyter, 2014, ISBN 978-3-11-037062-1 , p. 29.
  3. ↑ Sayir, businessman: engineering mechanics. Springer, 2015, 2nd edition, p. 9.
  4. ^ R. Mahnken: Textbook of technical mechanics. Volume 1: Statics. Springer, 2012, p. 5.
  5. ↑ a b Georg Hamel : Elementary Mechanics . A textbook. BG Teubner, Leipzig and Berlin 1912, p. 74 ( archive.org [accessed February 26, 2020]).
  6. ↑ Wolfgang Nolting: Basic Course Theoretical Physics 2. Analytical Mechanics. 9th edition, p. IX, 105 f.
  7. ↑ Honerkamp, ​​Römer: Classical Theoretical Physics. 4th edition, foreword and p. 69.
  8. ↑ Hans Rick: Gas turbines and aircraft propulsion. Springer, 2013, p. 35.
  9. ↑ Dinkler: Basics of structural engineering. 4th edition. Springer, 2016, p. 3.
  10. ^ Peter Marti : structural analysis. Ernst & Sohn , 2012, p. 4.
  11. ^ Peter Marti: structural analysis. Ernst & Sohn, 2012, p. 1.
  12. ^ Karl-Eugen Kurrer : History of structural engineering. In search of balance . Ernst & Sohn, 2016, p. 15