Terms starting with S
72 terms · page 1 of 3
Saha Ionization Equation
A thermodynamic relation expressing the ionization state of a plasma in thermal equilibrium as a function of temperature and electron…
Foundations of PhysicsScalar
A physical quantity that is completely specified by its magnitude (value and unit) alone, possessing no direction.
Foundations of PhysicsScalar Product
An algebraic vector operation that multiplies two vectors to yield a scalar equal to the product of their magnitudes and the cosine of the…
Quantum & Atomic PhysicsSchrödinger Equation
A fundamental partial differential equation describing how the quantum wave function of a physical system evolves deterministically over…
Astrophysics, Cosmology & RelativitySchwarzschild Radius
The physical radius defining the event horizon of a non-rotating, spherically symmetric black hole of mass M.
Foundations of PhysicsScientific Law
A concise verbal or mathematical statement that describes a universal, consistently observed relationship in nature under specified…
Foundations of PhysicsScientific Method
An empirical, iterative process for investigating natural phenomena through observation, hypothesis formulation, experimentation, and…
Foundations of PhysicsScientific Notation
A standardized method of expressing very large or very small numbers in the format a × 10ⁿ, where 1 ≤ |a| < 10 and n is an integer.
Foundations of PhysicsScientific Theory
A comprehensive, well-substantiated explanation of a broad aspect of nature supported by extensive empirical evidence and repeated testing.
Nuclear & Particle PhysicsScintillation Counter
A radiation detection instrument that measures ionizing radiation by detecting flashes of light (scintillations) produced in a luminescent…
Geophysics & Environmental PhysicsSea Level Rise
The ongoing increase in global mean sea level caused by thermal expansion of warming ocean water and meltwater input from glaciers and ice…
Geophysics & Environmental PhysicsSeafloor Spreading
The tectonic process occurring at mid-ocean ridges where new oceanic crust is created by upwelling mantle magma and moves laterally away.
Thermodynamics & Statistical PhysicsSecond Law of Thermodynamics
The law asserting that spontaneous physical processes increase total entropy in isolated systems, placing fundamental limits on heat engine…
Condensed Matter & Materials PhysicsSeebeck Effect
The direct conversion of a temperature gradient into an electrical voltage across a conductor or semiconductor.
Geophysics & Environmental PhysicsSeismic Waves (P & S Waves)
Elastic body waves that propagate through Earth's interior during an earthquake, classified as Primary (P) waves and Secondary (S) waves.
Geophysics & Environmental PhysicsSeismology
The scientific study of earthquakes and the propagation of mechanical elastic waves through the Earth's interior and surface layers.
Quantum & Atomic PhysicsSelection Rules
A set of quantum mechanical rules constraining allowed radiative transitions between atomic energy states.
Electromagnetism & ElectronicsSelf-Inductance
The property of an electrical conductor or coil whereby a change in current induces an opposing electromotive force in the conductor itself.
Condensed Matter & Materials PhysicsSemiconductor
A class of crystalline solids possessing electrical conductivity between that of conductors and insulators, controllable by temperature…
Electromagnetism & ElectronicsSemiconductor Diode
A two-terminal semiconductor device formed by a p-n junction that allows electric current to flow easily in one direction while blocking it…
Electromagnetism & ElectronicsSeries Circuit
An electrical circuit topology in which components are connected end-to-end sequentially along a single continuous current path.
Condensed Matter & Materials PhysicsShape Memory Alloys
A class of smart metallic alloys that can be deformed when cold, but return to their original pre-deformed shape when heated above a…
Waves, Oscillations & AcousticsShock Wave
A extremely thin propagating pressure disturbance characterized by a nearly instantaneous jump in pressure, temperature, and density.
Foundations of PhysicsSI Units
The International System of Units (SI), the modern metric system used globally as the standard language of science and measurement.