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 20 of 32: from “NPN” to “paste”.
- NPN noun Ellipsis of NPN transistor.
- nuclear isomer noun Any of two or more atomic nuclei with the same mass number and atomic number but with different radioactive properties
- nuclear reactor noun Any device in which a controlled chain reaction is maintained for the purpose of creating heat (for power generation) or for creating…
- nuclear response function noun A relationship that describes the probability of a particle that collides with another being scattered in any particular manner
- nuclear spectrum noun The distribution of the intensity of particles or radiation emitted in a nuclear process as a function of energy - a unique signature of…
- nucleation noun The first stage of a phase transition in a small region.
- nucleo- prefix Forming words pertaining to atomic nuclei.
- nucleonics noun The study of nucleons, or of atomic nuclei
- nucleus noun The massive, positively charged central part of an atom, made up of protons and neutrons.
- nutation noun A bobbing motion that accompanies the precession of a spinning rigid body.
- objectivation noun An interpretation of a quantum mechanical concept in terms of classical physics.
- oblique shock noun A shock wave that, unlike a normal shock, is inclined with respect to the incident upstream flow direction.
- observable noun Any physical property that can be observed and measured directly and not derived from other properties.
- occlusion noun The absorption of a gas or liquid by a substance such as a metal.
- occupation number noun The numerical extent to which a quantum state is filled (in a system of many, identical quantum particles)
- octopole noun A multipole configuration with eight equal charges arranged in a circular pattern.
- octupole noun Anything having eight poles or electrodes, but especially a kind of magnet used for controlling beams of charged particles
- off time noun The time interval when no current flows.
- ogive noun The pointed, curved nose of a bullet, missile, or rocket.
- ohmic resistance noun That portion of the apparent resistance or impedance of a circuit which depends only upon the dimensions of the conductors, their…
- ol noun open line (open circuit, no continuity).
- omega noun Angular velocity; symbol: ω.
- omnidirectional adj Having a ring-shaped radiation pattern, with equal radiation in all azimuthal directions.
- on silent adj A setting on an electronic device that prevents it from producing noise when it receives a call or a message, such as an alert or a…
- one shot noun A monostable multivibrator.
- onium noun The bound pair of a particle and its antiparticle.
- opacity noun A measure of relative impenetrability to electromagnetic radiation such as light.
- opalescence noun the milky iridescent appearance of a dense transparent medium when it is illuminated by polychromatic visible radiation (such as sunlight)…
- open noun A defect in an electrical circuit preventing current from flowing.
- open system noun A system that can exchange both matter and energy with its surroundings.
- optic adj Of, or relating to optics or optical instruments.
- optical activity noun a property caused by asymmetrical molecular or crystal structure that enables a compound or crystal to rotate the plane of incident…
- optical depth noun The natural logarithm of the ratio of amount of radiation that hits an object to the amount of radiation that emerges from that object on…
- optical flat noun A disk of high-quality quartz glass having at least one side ground and polished with a deviation in flatness less than 50 nanometers all…
- optical rotation noun The rotation of the plane of polarization of plane polarized light as it passes through a chiral medium
- optical spectrum noun The distribution of colours produced when white light passes through a prism.
- optics noun The physics of light and vision: basic optical science.
- optoelectronics noun The branch of physics that deals with the interaction of light with electronic devices, or the production of light from such devices
- or conj A logic gate to implement inclusive or.
- orbit noun The path of an electron around an atomic nucleus.
- orbital noun A specification of the energy and probability density of one or more electrons at any point in an atom or molecule, representable as a wave…
- orbital symmetry noun The properties of an atomic orbital or molecular orbital that characterize its symmetry; especially those properties that are conserved in…
- orbitally adv By means of or in relation to an orbital or orbitals
- orbiton noun A quasiparticle, corresponding to the orbital energy of an electron, which can result from an electron apparently ‘splitting’ under certain…
- order noun A power of polynomial function in an electronic circuit’s block, such as a filter, an amplifier, etc.
- ortho- prefix Of any molecule of the form X₂ in which the two nuclei have parallel spin.
- orthohelium noun form of the helium atom in which the spins of the two electrons form a triplet state (a state with definite total spin).
- orthohydrogen noun form of the hydrogen molecule (H₂) in which the two nuclei have parallel spin; about 75% of natural hydrogen
- orthokinetic adj Describing any property related to the kinetic energy imparted by collisions with other bodies
- oscillometer noun Any of several devices that measure oscillations
- out of power prep_phrase Lacking electrical power.
- out-of-battery adj In battery-powered electronics, devoid of any power.
- outcouple verb To remove the coupling between two interacting beams of laser light
- output noun The amount of power produced by a particular system.
- outscatter verb To scatter outward.
- overclose verb To form a closed universe before it has attained its present age.
- overcurrent protective device noun A device, usually a fuse, polyfuse, or circuit breaker, intended to detect and stop an overcurrent condition.
- overfogged adj Having a focal point that is in front of the retina or observer; myopic.
- overpotential noun The difference between the electric potential of an electrode or cell under the passage of a current and the thermodynamic value of the…
- overpulse noun An electric pulse that spikes above normal operating levels.
- overscaling noun Adjustment of a parameter to exceed a normal limit
- overtone noun A tone whose frequency is an integer multiple of another; a member of the harmonic series.
- overtrip noun An instance of overtripping.
- overvoltage noun The difference between the electric potential of an electrode or cell under the passage of a current and the thermodynamic value of the…
- oxidaniumyl noun The cation H₂O⁺, present in interstellar space, formed by removal of an electron from a water molecule
- oxygen burning noun The nucleosynthesis process, subsequent to carbon burning, in which neon disintegrates to oxygen which subsequently fuses to form silicon…
- oxygen-16 noun The major stable isotope of oxygen, 168O, having eight protons and eight neutrons; it amounts to over 99% of the element in nature
- oxygen-17 noun A rare stable isotope of oxygen, 178O, having eight protons and nine neutrons; it amounts to 0.037% of the element in nature
- oxygen-18 noun A stable isotope of oxygen, 188O, with 8 protons and 10 neutrons; it amounts to about 0.2% of the element in nature
- oxygenlike adj Having the same electronic structure as an oxygen atom
- p noun Abbreviation of proton.
- p-n junction noun An interface between a p-type and n-type semiconductor; used to create junction diodes and junction transistors
- p-type adj (Of a semiconductor) in which conduction is due to the movement of positive holes rather than electrons.
- pad noun The amount by which a signal has been reduced.
- pad down verb To reduce a signal.
- pairing energy noun The extra binding energy associated with pairs of nucleons of the same kind; this results in nuclei having odd numbers of protons or…
- pantogen noun A hypothetical fundamental substance supposed by Gustavus Detlef Hinrichs to form all other substances.
- pantoscopic adj Designed to focus on both near and distant objects at the same time, typically by means of a tilt in the lens
- parahelium noun The form of the helium atom in which the spins of the two electrons form a singlet state (a state with zero total spin)
- parahydrogen noun The form of the hydrogen molecule (H₂) in which the two nuclei have antiparallel spin; about 25% of hydrogen at room temperature.
- parallax motion noun The apparent motion of a tracking-locked foreground object against a background, when the camera is moving across the environment. (ie. A…
- paramagnetism noun The tendency of magnetic dipoles to align with an external magnetic field; materials that exhibit this tendency become temporary magnets.
- paranematic adj Describing the production of nematic order in a liquid crystal under the influence of an applied magnetic field
- parasitic noun A component of a circuit that does not show up in a circuit's schematic but does show up in the circuit's behavior.
- parasitic element noun A circuit element or property that is present within an electrical component, and has a negative effect on the performance of the circuit.
- paraxial adj Near an optical axis.
- parent noun The nuclide that decays into a daughter nuclide.
- parity noun Symmetry of interactions under spatial inversion.
- partial charge noun an electric charge that is less than the charge on an electron; for example, that of a quark
- particle noun Any of various physical objects making up the constituent parts of an atom; an elementary particle or subatomic particle.
- particle beam noun A beam of atoms, ions or subatomic particles that has been accelerated by some device and collimated by magnets and/or electrostatic lenses
- particle shower noun A group of secondary particles that splits off from matter when a high-energy particle interacts with it.
- partition function noun generalization of the definition of a partition function in statistical mechanics
- parton noun Any of the constituent particles making up a compound particle, e.g. the quarks and gluons which make up hadrons.
- Paschen-Back effect noun A form of the Zeeman effect that affects the spectral lines obtained when a light source is placed in a very strong magnetic field.
- pass transistor noun A transistor used as a switch to pass logic levels between nodes of a circuit, instead of as a switch connected directly to a supply…
- passive noun Any component that consumes but does not produce energy, or is incapable of power gain.
- passive gravitational mass noun The mass of an object measured via the gravitational force experienced by it in a known gravitational field
- passthrough noun As of a signal through a device or network.
- paste noun A substance that behaves as a solid until a sufficiently large load or stress is applied, at which point it flows like a fluid.