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Thermodynamics - Wikipedia, the free encyclopedia
Annotated color version of the original 1824 Carnot heat engine showing the hot body (boiler), working body (system, steam), and cold body (water), the letters labeled according to the stopping points in Carnot cycle . Thermodynamics is the branch of physical science concerned with heat and its relation to other forms of energy and work . It defines macroscopic variables (such as temperature , entropy , and pressure ) that describe average properties of material bodies and radiation, and explains how they are related and by what laws they change with time.Statics - Wikipedia, the free encyclopedia
Statics is the branch of mechanics concerned with the analysis of loads ( force , torque/moment ) on physical systems in static equilibrium , that is, in a state where the relative positions of subsystems do not vary over time, or where components and structures are at a constant velocity. When in static equilibrium, the system is either at rest, or its center of mass moves at constant velocity. By Newton's first law , this situation implies that the net force and net torque (also known as moment of force) on every part of the system is zero. From this constraint, such quantities as stress or pressure can be derived. The net forces equaling zero is known as the first condition for equilibrium, and the net torque equaling zero is known as the second condition for equilibrium. See statically determinate .
Theory of relativity - Wikipedia, the free encyclopedia
The theory of relativity , or simply relativity , encompasses two theories of Albert Einstein : special relativity and general relativity . [ 1 ] The basic overall concept is that both time and space are relative, not fixed. However, the word relativity is sometimes used in reference to Galilean invariance . The term "theory of relativity" was based on the expression "relative theory" ( German : Relativtheorie ) used by Max Planck in 1906, who emphasized how the theory uses the principle of relativity . In the discussion section of the same paper Alfred Bucherer used for the first time the expression "theory of relativity" ( German : Relativitätstheorie ). [ 2 ] [ 3 ] The theory of relativity transformed theoretical physics and astronomy during the 20th century.
Quantum mechanics (QM - also known as quantum physics , or quantum theory ) is a branch of physics dealing with physical phenomena where the action is on the order of the Planck constant . Quantum mechanics departs from classical mechanics primarily at the atomic and subatomic scales, the so-called " quantum realm ". QM provides a mathematical description of much of the dual particle-like and wave-like ("wavicle") behavior and interactions of energy and matter . In advanced topics of quantum mechanics, some of these behaviors are macroscopic and only emerge at extreme (i.e. very low or very high) energies or temperatures .
Quantum mechanics - Wikipedia, the free encyclopedia
Plasma (physics) - Wikipedia, the free encyclopedia
Plasma lamp , illustrating some of the more complex phenomena of a plasma, including filamentation . The colors are a result of relaxation of electrons in excited states to lower energy states after they have recombined with ions. These processes emit light in a spectrum characteristic of the gas being excited. In physics and chemistry , plasma is a state of matter similar to gas in which a certain portion of the particles are ionized . Heating a gas may ionize its molecules or atoms (reduce or increase the number of electrons in them), thus turning it into a plasma, which contains charged particles: positive ions and negative electrons or ions. [ 1 ] Ionization can be induced by other means, such as strong electromagnetic field applied with a laser or microwave generator, and is accompanied by the dissociation of molecular bonds , if present. [ 2 ]
Optics is the branch of physics which involves the behavior and properties of light , including its interactions with matter and the construction of instruments that use or detect it. [ 1 ] Optics usually describes the behavior of visible , ultraviolet , and infrared light. Because light is an electromagnetic wave , other forms of electromagnetic radiation such as X-rays , microwaves , and radio waves exhibit similar properties. [ 1 ] Most optical phenomena can be accounted for using the classical electromagnetic description of light.
Optics - Wikipedia, the free encyclopedia
Mechanics ( Greek Μηχανική ) is the branch of physics concerned with the behavior of physical bodies when subjected to forces or displacements , and the subsequent effects of the bodies on their environment. The discipline has its roots in several ancient civilizations (see History of classical mechanics and Timeline of classical mechanics ). During the early modern period , scientists such as Galileo , Kepler , and especially Newton , laid the foundation for what is now known as classical mechanics . It is a branch of classical physics that deals with the particles that are moving either with less velocity or that are at rest.
Mechanics - Wikipedia, the free encyclopedia
Mathematical physics - Wikipedia, the free encyclopedia
Mathematical physics refers to development of mathematical methods for application to problems in physics . The Journal of Mathematical Physics defines this area as: "the application of mathematics to problems in physics and the development of mathematical methods suitable for such applications and for the formulation of physical theories." [ 1 ] . [ edit ] Scope of the subject
Kinematics - Wikipedia, the free encyclopedia
Kinematics is the branch of classical mechanics that describes the motion of points, bodies (objects) and systems of bodies (groups of objects) without consideration of the forces that cause it. [ 1 ] [ 2 ] [ 3 ] The term is the English version of A.M. Ampère 's cinématique, [ 4 ] which he constructed from the Greek κίνημα , kinema (movement, motion), derived from κινεῖν , kinein (to move). [ 5 ] [ 6 ] The study of kinematics is often referred to as the geometry of motion. [ 7 ] (See analytical dynamics for more detail on usage). To describe motion, kinematics studies the trajectories of points, lines and other geometric objects and their differential properties such as velocity and acceleration.
Typical aerodynamic teardrop shape, assuming a viscous medium passing from left to right, the diagram shows the pressure distribution as the thickness of the black line and shows the velocity in the boundary layer as the violet triangles. The green vortex generators prompt the transition to turbulent flow and prevent back-flow also called flow separation from the high pressure region in the back. The surface in front is as smooth as possible or even employs shark like skin , as any turbulence here will reduce the energy of the airflow. The truncation on the right, known as a Kammback , also prevents back flow from the high pressure region in the back across the spoilers to the convergent part. In physics , fluid dynamics is a sub-discipline of fluid mechanics that deals with fluid flow —the natural science of fluids ( liquids and gases ) in motion.
Fluid dynamics - Wikipedia, the free encyclopedia
Electromagnetism - Wikipedia, the free encyclopedia
Electromagnetism is the branch of science concerned with the forces that occur between electrically charged particles. In electromagnetic theory these forces are explained using electromagnetic fields . Electromagnetic force is one of the four fundamental interactions in nature , the other three being the strong interaction , the weak interaction and gravitation . Electromagnetism is the interaction responsible for practically all the phenomena encountered in daily life, with the exception of gravity. Ordinary matter takes its form as a result of intermolecular forces between individual molecules in matter.In the field of physics , the study of the causes of motion and changes in motion is dynamics . In other words the study of forces and why objects are in motion . Dynamics includes the study of the effect of torques on motion.
Dynamics (mechanics) - Wikipedia, the free encyclopedia
Physical cosmology - Wikipedia, the free encyclopedia
Physical cosmology , as a branch of astronomy , is the study of the largest-scale structures and dynamics of the universe and is concerned with fundamental questions about its formation and evolution. [ 1 ] For most of human history, it was a branch of metaphysics and religion . Cosmology as a science originated with the Copernican principle , which implies that celestial bodies obey identical physical laws to those on Earth, and Newtonian mechanics , which first allowed us to understand those laws. Physical cosmology, as it is now understood, began with the twentieth century development of Albert Einstein 's general theory of relativity and better astronomical observations of extremely distant objects. These advances made it possible to speculate about the origin of the universe , and allowed scientists to establish the Big Bang Theory as the leading cosmological model.Condensed matter physics deals with the physical properties of condensed phases of matter . [ 1 ] These properties appear when a number of atoms at the supramolecular and macromolecular scale interact strongly and adhere to each other or are otherwise highly concentrated in a system. The most familiar condensed phases are solids and liquids , which arise from electromagnetic binding forces. More exotic condensed phases include the mesophases of liquid crystal devices, the superconducting phase exhibited by certain materials at low temperature , the ferromagnetic and antiferromagnetic phases of spins on atomic lattices , and the Bose-Einstein condensate found in certain ultracold atomic systems.