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Classical Mechanics

Motion, forces, and energy at everyday scales

Physics: Gravity

Gravity In physics, gravity (from Latin gravitas 'weight'), also known as gravitation or a gravitational interaction, is a fundamental interaction, which may be described as the force that draws mat...

Physics: Newton's laws of motion

Newton's laws of motion Newton's laws of motion are three physical laws that describe the relationship between the motion of an object and the forces acting on it....

Physics: Force

Force In physics, a force is an action that can cause an object to change its velocity or its shape, or to resist other forces, or to cause changes of pressure in a fluid....

Physics: Momentum

Momentum In Newtonian mechanics, momentum (pl....

Physics: Acceleration

Acceleration In mechanics, an acceleration is a change in velocity and is calculated as the rate of change of the velocity of an object with respect to time....

Physics: Cavendish experiment

Cavendish experiment By: Henry Cavendish (1797) The Cavendish experiment, performed in 1797–1798 by English scientist Henry Cavendish, was the first experiment to measure the force of gravity between...

Physics: Velocity

Velocity Velocity is a measurement of speed in a certain direction of motion....

Physics: Newton's law of universal gravitation

Newton's law of universal gravitation Newton's law of universal gravitation describes gravity as a force by stating that every particle attracts every other particle in the universe with a force that...

Physics: Time dilation

Time dilation Time dilation is the difference in elapsed time as measured by two clocks, either because of a relative velocity, a consequence of special relativity, or a difference in gravitational p...

Physics: Black hole

Black hole A black hole is an astronomical body so compact that its gravity prevents anything, including light, from escaping....

Physics: Foucault pendulum

Foucault pendulum By: Leon Foucault (1851) The Foucault pendulum or Foucault's pendulum is a simple device named after French physicist Léon Foucault, conceived as an experiment to demonstrate the Ea...

Physics: Archimedes' principle

Archimedes' principle Archimedes' principle states that the upward buoyant force that is exerted on a body immersed in a fluid, whether fully or partially, is equal to the weight of the fluid that th...

Physics: Johannes Kepler

Johannes Kepler (1571) Johannes Kepler (27 December 1571 – 15 November 1630) was a German polymath who was an astronomer, mathematician, astrologer, natural philosopher and music theorist....

Physics: Eötvös experiment

Eötvös experiment By: Lorand Eotvos (1885) The Eötvös experiment was a physics experiment that measured the correlation between inertial mass and gravitational mass, demonstrating that the two were o...

Physics: Hooke's law

Hooke's law In physics, Hooke's law is an empirical law which states that the force (F) needed to extend or compress a spring by some distance (x) scales linearly with respect to that distance—that i...

Physics: Molecule

Molecule A molecule is a group of two or more atoms that are held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this c...

Physics: Temperature

Temperature In classical thermodynamics and kinetic theory, temperature reflects the average kinetic energy of the particles in a system, providing a quantitative measure of how energy is distributed...

Physics: Isaac Newton

Isaac Newton (1643) Sir Isaac Newton ( ; 4 January [O....

Physics: Kepler's laws of planetary motion

Kepler's laws of planetary motion In astronomy, Kepler's laws of planetary motion give good approximations for the orbits of planets around the Sun....

Physics: Pressure

Pressure Pressure (symbol: p or P) is the force applied perpendicular to the surface of an object per unit area over which that force is distributed....

Physics: Daniel Bernoulli

Daniel Bernoulli (1700) Daniel Bernoulli ( bur-NOO-lee; Swiss Standard German: [ˈdaːni̯eːl bɛrˈnʊli]; 8 February [O....

Physics: Michelson–Morley experiment

Michelson–Morley experiment By: Michelson and Morley (1887) The Michelson–Morley experiment was an attempt to measure the motion of the Earth relative to the luminiferous aether, a supposed medium pe...

Physics: Heat

Heat In thermodynamics, heat is defined as the form of energy crossing the boundary of a thermodynamic system by virtue of a temperature difference across the boundary....

Physics: Conservation of momentum

Conservation of momentum In Newtonian mechanics, momentum (pl....

Physics: Entropy

Entropy Entropy is a scientific concept, most commonly associated with states of disorder, randomness, or uncertainty....

Physics: Gravity well

Gravity well A sphere of influence (SOI) in astrodynamics and astronomy is the oblate spheroid-shaped region where a particular celestial body exerts the main gravitational influence on an orbiting o...

Physics: Orbit

Orbit In celestial mechanics, an orbit is the curved trajectory of an object under the influence of an attracting force....

Physics: Conservation of angular momentum

Conservation of angular momentum Angular momentum (sometimes called moment of momentum or rotational momentum) is the rotational analog of linear momentum....

Physics: Aspect's experiment

Aspect's experiment By: Alain Aspect (1982) Aspect's experiment was the first quantum mechanics experiment to demonstrate the violation of Bell's inequalities with photons using distant detectors....

Physics: Pascal's law

Pascal's law Pascal's law (also Pascal's principle or the principle of transmission of fluid-pressure) is a principle in fluid mechanics that states that a pressure change at any point in a confined ...

Physics: Bernoulli's principle

Bernoulli's principle Bernoulli's principle is a key concept in fluid dynamics that relates pressure, speed and height....

Physics: Neutrino

Neutrino A neutrino ( new-TREE-noh; denoted by the Greek letter ν) is an elementary particle that interacts via the weak interaction and gravity....

Physics: Torricelli's theorem

Torricelli's theorem Torricelli's law, also known as Torricelli's theorem, is a theorem in fluid dynamics relating the speed of fluid flowing from a hole to the height of fluid above the hole....

Physics: Standard Model

Standard Model The Standard Model of particle physics is the theory describing three of the four known fundamental forces (electromagnetic, weak and strong interactions – excluding gravity) in the un...

Physics: Stokes' law

Stokes' law In fluid dynamics, Stokes' law gives the frictional force – also called drag force – exerted on spherical objects moving at very small Reynolds numbers in a viscous fluid....

Physics: Gravitational wave

Gravitational wave Gravitational waves are waves of spacetime curvature that propagate at the speed of light and are produced by the relative motion of gravitating masses....

Physics: Laws of thermodynamics

Laws of thermodynamics The laws of thermodynamics are a set of scientific laws which define a group of physical quantities, such as temperature, energy, and entropy, that characterize thermodynamic s...

Physics: Galaxy

Galaxy A galaxy is a system of stars, stellar remnants, interstellar gas, dust, and dark matter bound together by gravity....

Physics: Zeroth law of thermodynamics

Zeroth law of thermodynamics The zeroth law of thermodynamics is one of the four principal laws of thermodynamics....

Physics: First law of thermodynamics

First law of thermodynamics The first law of thermodynamics is a formulation of the law of conservation of energy in the context of thermodynamic processes....

Physics: Second law of thermodynamics

Second law of thermodynamics The second law of thermodynamics is a physical law based on universal empirical observation concerning heat and energy interconversions....

Physics: Resonance

Resonance Resonance is a phenomenon that occurs when an object or system is subjected to an external force or vibration whose frequency matches a resonant frequency (or resonance frequency) of the s...

Physics: Stern–Gerlach experiment

Stern–Gerlach experiment By: Stern and Gerlach (1922) In quantum physics, the Stern–Gerlach experiment demonstrated that the spatial orientation of angular momentum is quantized....

Physics: Third law of thermodynamics

Third law of thermodynamics The third law of thermodynamics states that the entropy of a closed system at thermodynamic equilibrium approaches a constant value when its temperature approaches absolut...

Physics: Max Born

Max Born (1882) Max Born (German: [ˈmaks ˈbɔʁn] ; 11 December 1882 – 5 January 1970) was a German–British theoretical physicist who was instrumental in the development of quantum mechanics....

Physics: Dispersion (optics)

Dispersion (optics) Dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency....

Physics: Kinetic energy

Kinetic energy In physics, the kinetic energy of an object is the form of energy that it possesses due to its motion....

Physics: Satyendra Nath Bose

Satyendra Nath Bose (1894) Satyendra Nath Bose (; 1 January 1894 – 4 February 1974) was an Indian theoretical physicist and mathematician....

Physics: Work (physics)

Work (physics) In science, work is the energy transferred to or from an object via the application of force along a displacement....

Physics: Werner Heisenberg

Werner Heisenberg (1901) Werner Karl Heisenberg (; German: [ˈvɛʁnɐ ˈhaɪzn̩bɛʁk] ; 5 December 1901 – 1 February 1976) was a German theoretical physicist, one of the main pioneers of the theory of quan...

Physics: Paul Dirac

Paul Dirac (1902) Paul Adrien Maurice Dirac ( dih-RAK; 8 August 1902 – 20 October 1984) was a British theoretical physicist who is considered to be one of the founders of quantum mechanics....

Physics: Wolfgang Pauli

Wolfgang Pauli (1900) Wolfgang Ernst Pauli ( PAW-lee; German: [ˈpaʊ̯li] ; 25 April 1900 – 15 December 1958) was an Austrian–Swiss theoretical physicist and a pioneer of quantum mechanics....

Physics: Electromagnetic induction

Electromagnetic induction Electromagnetic induction or magnetic induction is the production of an electromotive force (emf) across an electrical conductor in a changing magnetic field....

Physics: Synchrotron radiation

Synchrotron radiation Synchrotron radiation (also known as magnetobremsstrahlung) is the electromagnetic radiation emitted when relativistic charged particles are subject to an acceleration perpendic...

Physics: Superfluidity

Superfluidity Superfluidity is the characteristic property of a fluid with zero viscosity which therefore flows without any loss of kinetic energy....

Physics: Mach number

Mach number The Mach number (M or Ma), often only Mach (; German: [max]), is a dimensionless quantity in fluid dynamics representing the ratio of flow velocity past a boundary to the local speed of s...

Physics: Terminal velocity

Terminal velocity Terminal velocity is the maximum speed attainable by an object as it falls through a fluid (air is the most common example)....

Physics: Viscosity

Viscosity When two fluid layers move relative to each other, a friction force develops between them and the slower layer acts to slow down the faster layer....

Physics: Coulomb's law

Coulomb's law Coulomb's inverse-square law, or simply Coulomb's law, is an experimental law of physics that calculates the amount of force between two electrically charged particles at rest....

Physics: Capillary action

Capillary action Capillary action (sometimes called capillarity, capillary motion, capillary rise, capillary effect, or wicking) is the process of a liquid flowing in a narrow space without the assis...

Physics: Buoyancy

Buoyancy Buoyancy (), or upthrust, is the force exerted by a fluid opposing the weight of a partially or fully immersed object (which may also be a parcel of fluid)....

Physics: Centripetal force

Centripetal force Centripetal force (from Latin centrum 'center' and petere 'to seek') is the force that makes a body follow a curved path....

Physics: Angular momentum

Angular momentum Angular momentum (sometimes called moment of momentum or rotational momentum) is the rotational analog of linear momentum....

Physics: Torque

Torque In physics and mechanics, torque is the rotational correspondent of linear force....

Physics: Simple harmonic motion

Simple harmonic motion In mechanics and physics, simple harmonic motion (sometimes abbreviated as SHM) is a special type of periodic motion an object experiences by means of a restoring force whose m...

Physics: Pendulum

Pendulum A pendulum is a device made of a weight suspended from a pivot so that it can swing freely....

Physics: Spring (device)

Spring (device) A spring is a device consisting of an elastic but largely rigid material (typically metal) bent or molded into a form (especially a coil) that can return into shape after being compre...

Physics: Gravity Probe B

Gravity Probe B By: NASA / Stanford (2004) Gravity Probe B (GP-B) was a satellite-based experiment whose objective was to test two previously-unverified predictions of general relativity: the geodeti...

Physics: Maxwell's equations

Maxwell's equations Maxwell's equations are a set of coupled partial differential equations that, together with the Lorentz force law, form the foundation of classical electromagnetism, classical opt...

Physics: 1932 Nobel Prize in Physics

1932 Nobel Prize in Physics Awarded to: Werner Karl Heisenberg The creation of quantum mechanics, the application of which has, inter alia, led to the discovery of the allotropic forms of hydrogen....

Physics: Uncertainty principle

Uncertainty principle The uncertainty principle, also known as Heisenberg's indeterminacy principle, is a fundamental concept in quantum mechanics....

Physics: Pauli exclusion principle

Pauli exclusion principle In quantum mechanics, the Pauli exclusion principle (German: Pauli-Ausschlussprinzip) states that two or more identical particles with half-integer spins (i....

Physics: Philip Anderson

Philip Anderson (1923) Michael Phillip Anderson (December 25, 1959 – February 1, 2003) was a United States Air Force officer and NASA astronaut....

Physics: De Broglie hypothesis

De Broglie hypothesis Matter waves are a central part of the theory of quantum mechanics, being half of wave–particle duality....

Physics: Born rule

Born rule The Born rule is a postulate of quantum mechanics that gives the probability that a measurement of a quantum system will yield a given result....

Physics: General relativity

General relativity General relativity, also known as the general theory of relativity, and as Einstein's theory of gravity, is the geometric theory of gravitation published by Albert Einstein in May ...

Physics: Equivalence principle

Equivalence principle The equivalence principle is the hypothesis that the observed equivalence of gravitational and inertial mass is a consequence of nature....

Physics: Lorentz transformation

Lorentz transformation In physics, the Lorentz transformations are a six-parameter family of linear transformations from a coordinate frame in spacetime to another frame that moves at a constant velo...

Physics: John Clauser

John Clauser (1942) John Francis Clauser (; born December 1, 1942) is an American theoretical and experimental physicist known for contributions to the foundations of quantum mechanics, in particular...

Physics: Lisa Randall

Lisa Randall (1962) Lisa Randall (born June 18, 1962) is an American theoretical physicist and Frank B....

Physics: 1949 Nobel Prize in Physics

1949 Nobel Prize in Physics Awarded to: Hideki Yukawa His prediction of the existence of mesons on the basis of theoretical work on nuclear forces....

Physics: Complementarity (physics)

Complementarity (physics) In physics, complementarity is a conceptual aspect of quantum mechanics that Niels Bohr regarded as an essential feature of the theory....

Physics: Wave–particle duality

Wave–particle duality Wave–particle duality is the concept in quantum mechanics that fundamental entities of the universe, like photons and electrons, exhibit particle or wave properties according to...

Physics: Noether's theorem

Noether's theorem Noether's theorem states that every continuous symmetry of the action of a physical system with conservative forces has a corresponding conservation law....

Physics: 1954 Nobel Prize in Physics

1954 Nobel Prize in Physics Awarded to: Max Born, Walther Bothe His fundamental research in quantum mechanics, especially for his statistical interpretation of the wavefunction / for the coincidence...

Physics: Bell's theorem

Bell's theorem Bell's theorem is a term encompassing a number of closely related results in physics, all of which determine that quantum mechanics is incompatible with local hidden-variable theories,...

Physics: 1965 Nobel Prize in Physics

1965 Nobel Prize in Physics Awarded to: Sin-Itiro Tomonaga, Julian Schwinger, Richard P. Feynman Their fundamental work in quantum electrodynamics, with deep-ploughing consequences for the physics o...

Physics: 1970 Nobel Prize in Physics

1970 Nobel Prize in Physics Awarded to: Hannes Olof Gösta Alfvén, Louis Eugène Félix Néel Fundamental work and discoveries in magnetohydro-dynamics with fruitful applications in different parts of p...

Physics: 1975 Nobel Prize in Physics

1975 Nobel Prize in Physics Awarded to: Aage Niels Bohr, Ben Roy Mottelson, Leo James Rainwater The discovery of the connection between collective motion and particle motion in atomic nuclei and the...

Physics: 1996 Nobel Prize in Physics

1996 Nobel Prize in Physics Awarded to: David M. Lee, Douglas D. Osheroff, Robert C. Richardson Their discovery of superfluidity in helium-3....

Physics: 1998 Nobel Prize in Physics

1998 Nobel Prize in Physics Awarded to: Robert B. Laughlin, Horst L. Störmer, Daniel C. Tsui Their discovery of a new form of quantum fluid with fractionally charged excitations....

Physics: 2003 Nobel Prize in Physics

2003 Nobel Prize in Physics Awarded to: Alexei Alexeyevich Abrikosov, Vitaly Lazarevich Ginzburg, Anthony J. Leggett Pioneering contributions to the theory of superconductors and superfluids....

Physics: 2019 Nobel Prize in Physics

2019 Nobel Prize in Physics Awarded to: James Peebles, Michel Mayor, Didier Queloz Theoretical discoveries in physical cosmology / for the discovery of an exoplanet orbiting a solar-type star....

Physics: 2023 Nobel Prize in Physics

2023 Nobel Prize in Physics Awarded to: Pierre Agostini, Ferenc Krausz, Anne L’Huillier Experimental methods that generate attosecond pulses of light for the study of electron dynamics in matter....