This page gathers the 3,177 dictionary entries belonging to the domain “Physics”, as labelled by Wiktionary. Each word leads to its full entry: definitions, etymology, pronunciation, examples. Page 31 of 32: from “twistor” to “vorticity”.
- twistor noun Any of the complex-valued coordinates in twistor theory, which maps the geometric objects of conventional 3+1 space-time into geometric…
- twistronics noun The study of any of various electronic, optical and mechanical characteristics of two-dimensional materials (such as graphene) associated…
- twitter noun Unwanted flicker that occurs in interlaced displays when the image contains vertical detail that approaches the horizontal resolution of…
- two-way switch noun A plain type of light switch that can control lights, or other electrical loads, from a single location; a single-throw switch.
- Tyndall effect noun The visible scattering of light along the path of a beam caused by discontinuities such as suspended particles.
- ultra large scale integration noun An integration type for digital circuits that contain more than one million transistors providing hundreds of thousands of logic gates per…
- ultracold adj Of a temperature close to absolute zero, especially one at which quantum-mechanical properties are observed.
- ultraheavy adj Describing any atom that has a very large atomic weight; especially those that lie beyond fermium in the periodic table
- ultraperipheral adj Describing particle collisions in which no hadronic interactions occur because of the large spatial separation between the projectile and…
- ultrashort adj Having a wavelength of between 1 and 10 metres
- ultrasound noun Sound with a frequency greater than the upper limit of human hearing, which is approximately 20 kilohertz.
- ultraviolet adj Relating to very high energies or very small distances or time spans.
- ultraviolet catastrophe noun A fault in classical physics, from the Rayleigh's law/Rayleigh-Jeans law outcomes at short wavelengths/high frequencies, that causes…
- umklapp adj Pertaining to the transformation of a wave vector to another Brillouin zone as a result of a scattering process.
- unacoustic adj Having a frequency outside the range of audible sounds.
- unavailable energy noun Energy that is converted by an irreversible process into a form that is unavailable to do work.
- uncharged adj Not carrying an overall or net electric charge.
- uncharmed adj Having no charm quark
- unclocked adj Not measured or regulated by a clock; asynchronous.
- undamped adj Possessing a damping ratio of exactly zero.
- undercool verb To supercool
- undercooled adj supercooled
- underpotential noun A potential (for the deposition of a metal on a surface) that is greater than that predicted by the Nernst equation.
- unground verb To remove a connection to ground potential.
- ungrounded adj Not connected to ground potential
- unilateralization noun neutralization.
- uninterruptible power supply noun A device or system that almost instantaneously provides emergency power in the case that main power fails.
- unit noun One kilowatt-hour (as recorded on an electricity meter).
- unitless adj Having no units of measurement; such as a ratio or percentage of two numbers which have the same units.
- universality of freefall noun The principle that all objects fall with the same acceleration in a gravitational field, independent of their mass or composition.
- unlooper noun A device used to break a smart card's microcontroller out of an infinite loop state that makes it otherwise unusable.
- unpaired electron noun An electron, in an atomic orbital, for which there is no other electron in the same orbital but with opposite spin; a characteristic of…
- unparticle noun Used attributively to describe a form of physics that describes matter in terms other than of particles
- Unruh effect noun A theoretical prediction in quantum field theory that an observer who is uniformly accelerating through empty space will perceive a thermal…
- unstable adj Radioactive, especially with a short half-life.
- unswitched adj Directly connected without an intervening switch.
- up noun An up quark.
- up quark noun A quark having a fractional electric charge of +2/3 and a mass of about 1.5 to 4 MeV.
- upconversion noun The process by which two photons combine in a nonlinear medium to produce a higher-energy photon with a frequency that is the sum of those…
- upgoing adj Trending positive.
- UPS verb To connect a device to an uninterruptible power supply.
- upsilon noun An upsilon meson, or bottomonium.
- upsilon particle noun Any of a number of bound states of a heavy quark and its antiquark, especially that formed from a bottom quark and an anti-bottom quark.
- uranium-234 noun A radioactive isotope of uranium, 23492U, having a half-life of about 250,000 years; it accounts for about 55 parts per million of natural…
- uranium-235 noun A fissile isotope of uranium, used for energy generation and in atomic weapons, containing 143 neutrons. It has a half-life of 7.038×10⁸…
- uranium-238 noun A radioactive isotope of uranium, 23892U, having a half-life of 4.5 billion years; it accounts for about 99.3% of natural uranium.
- UTP noun unshielded twisted pair — a type of cable used for computer networking and telecommunications
- V particle noun Any heavy, unstable subatomic particle that decays into a pair of particles, thereby producing a characteristic letter V in a bubble…
- vacancy noun A defect in a crystal caused by the absence of an atom in a lattice
- vacuum noun A spacetime having tensors of zero magnitude.
- vacuum tube noun A type of electron tube that controls electron current through vacuum between electrodes within a sealed container, usually of glass or…
- valence band noun The highest range of electron energies in an insulator or semiconductor that can be populated; it corresponds to the valence electrons of…
- valleytronics noun A proposed equivalent of electronics using valleys in the valence band or conduction band structure of some semiconductors or insulators…
- value noun Any definite numerical quantity or other mathematical object, determined by being measured, computed, or otherwise defined.
- Van Allen radiation belt noun Either of two torus-shaped areas of high-energy charged particles which partly surround Earth, trapped by its magnetic field. The areas are…
- Van de Graaff generator noun A device in which an electric charge is built up on a large spherical electrode by means of a rapidly moving belt.
- van der Waals radius noun The radius of an imaginary hard sphere representing the distance of closest approach from one atom to another.
- van der Waals volume noun The volume occupied by an individual atom or molecule. For a single atom, it is the volume of a sphere whose radius is the van der Waals…
- van Stockum dust noun In general relativity, an exact solution of the Einstein field equation in which the gravitational field is generated by dust rotating…
- vanadium-50 noun The naturally-occurring radioactive isotope of vanadium, 5023V, having twenty-three protons and twenty-seven neutrons; its half-life is 1.5…
- var noun A unit of electrical power, in an AC circuit, equal to the power dissipated when 1 volt produces a current of 1 ampere.
- variance noun The number of degrees of freedom in a system.
- varistor noun An electronic component having a variable resistance; used to protect circuits against power surges.
- varitron noun An alleged subatomic particle with variable mass that Armenian physicists claimed to have discovered in the 1940s, but which was…
- VCC noun Common Collector Voltage; the positive supply voltage for an integrated circuit containing bipolar junction transistors.
- vector noun A directed quantity, one with both magnitude and direction; the signed difference between two points.
- velocity noun A vector quantity that denotes the rate of change of position with respect to time, combining speed with a directional component.
- vergence noun A measure of convergence or divergence of rays.
- vernier noun A secondary system of force application for the attitude control of a spacecraft; for example a vernier thruster.
- vertex noun The point where the surface of a lens crosses the optical axis.
- vertical alignment noun A style of liquid crystal display (LCD) that is naturally stored in an upright vertical position, producing a black image until an…
- very large scale integration noun An integration type for digital circuits that contain hundreds of thousands of transistors providing hundreds of thousands of logic gates…
- via noun A small hole in a printed circuit board filled with metal which connects two or more layers.
- vibration noun Any periodic process, especially a rapid linear motion of a body about an equilibrium position.
- vibrational energy noun The energy in a vibrating system, otherwise at rest; especially that in a molecule due to the vibrations of its atoms
- vinculum noun A horizontal line placed over a symbol or expression to denote logical negation (complement).
- violetward adj Toward the violet end of the spectrum.
- virtual adj Pertaining to a theoretical quality of something which would produce an observable effect if counteracting factors such as friction are…
- virtual focus noun A point from which light or other radiation apparently emanates, such as in the virtual image produced by a plane mirror.
- virtual particle noun a particle that exists for a limited time and space, introducing uncertainty in their energy and momentum
- viscoelasticity noun The property of a material that is both viscous and elastic.
- viscosity noun A quantity expressing the magnitude of internal friction in a fluid, as measured by the force per unit area resisting uniform flow.
- viscous adj Of or pertaining to viscosity.
- visible light noun The part of the electromagnetic spectrum, between infrared and ultraviolet, that is visible to the human eye.
- visible spectrum noun The portion of the electromagnetic spectrum which is visible to the human eye (red, orange, yellow, green, blue, and violet).
- vitreous adj Positive (of electric charge).
- VOC noun V_(OC): initialism of open-circuit voltage.
- voice coil noun A coil of wire attached to the apex of the cone of a loudspeaker that provides the motive force to the cone by the reaction of a magnetic…
- Voigt effect noun A magneto-optical phenomenon which rotates and elliptizes linearly polarised light sent into an optically active medium.
- volatile adj Evaporating or vaporizing readily under normal conditions.
- volta-electric adj Of or pertaining to voltaic electricity, i.e. electric currents, or voltaism, the chemical generation of electricity.
- voltage noun The difference in electrostatic potential between two points in space, especially between live and neutral conductors or the earth.
- voltage divider noun A type of simple electronic circuit which reduces any input voltage by a fixed factor using sources of impedance (such as resistors)…
- voltage multiplier noun An electronic circuit that provides an output voltage higher than the input voltage, by means of capacitors and diodes.
- voltammetry noun Any of several electrochemical analytical technique in which a current is measured as a voltage is varied.
- volumometer noun A device for measuring the volume of a solid by means of the pressure difference in a confined volume of gas caused by its presence or…
- von Kármán vortex street noun A double row of vortices in a fluid sometimes found in the wake of a cylindrical body (such as in a river, downstream of a bridge support)…
- vortex shedding noun An oscillating flow that occurs when a fluid flows past a bluff body at certain velocities. Vortices are created at the back of the body…
- vortex theory noun An obsolete scientific theory, chiefly developed by René Descartes, which attempted to explain celestial mechanics and the phenomena now…
- vorticity noun A property of a fluid flow related to local angular rotation; defined as the curl of the flow's velocity field.