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842 terms · page 26 of 36
Power Factor
The ratio of real power dissipated by an AC circuit to the apparent power delivered by the supply.
Electromagnetism & ElectronicsPoynting Vector
A vector representing the directional energy flux density (power per unit area) transported by an electromagnetic field.
Geophysics & Environmental PhysicsPrecession of the Equinoxes
The slow continuous conical rotation of Earth's rotational axis in space, taking ~25,800 years to complete one full cycle.
Foundations of PhysicsPrecision
The degree of agreement or repeatability among independent measurements of the same quantity taken under identical conditions.
OpticsPresbyopia
The age-related loss of accommodation power in the human eye caused by reduced elasticity of the crystalline lens.
Foundations of PhysicsPressure
The perpendicular force exerted per unit surface area over which that force is distributed.
Quantum & Atomic PhysicsPrincipal Quantum Number
The primary quantum number designating the main electron shell, overall orbital size, and principal energy level of an electron in an atom.
Thermodynamics & Statistical PhysicsPrinciple of Mixtures
The heat conservation principle stating that in an isolated system, heat lost by hotter components equals heat gained by cooler components…
Waves, Oscillations & AcousticsPrinciple of Superposition
The principle stating that when two or more linear waves overlap at a point, total resultant displacement equals vector sum of individual…
Quantum & Atomic PhysicsProbability Density
The probability per unit volume of finding a quantum particle at a specific spatial position at a given time.
Classical MechanicsProjectile Motion
The 2D motion of an object launched into a gravitational field under the sole influence of gravity (ignoring air resistance).
Astrophysics, Cosmology & RelativityProper Time
The physical time interval measured by a clock moving along a specific worldline through spacetime.
Biophysics & Medical PhysicsProtein Folding
The physical process by which a polypeptide chain folds spontaneously into a characteristic 3D functional native structure.
Biophysics & Medical PhysicsProton Therapy
An advanced form of external beam radiation therapy utilizing accelerated proton beams to destroy cancerous tumors.
Astrophysics, Cosmology & RelativityProtostar
An early evolutionary mass phase of a star formed by the gravitational contraction of an interstellar gas cloud before core hydrogen fusion…
Astrophysics, Cosmology & RelativityPulsar
A highly magnetized, rapidly rotating neutron star that emits focused beams of electromagnetic radiation from its magnetic poles.
Biophysics & Medical PhysicsPulse Oximetry
A non-invasive medical monitoring method measuring arterial blood oxygen saturation (SpO₂) using differential optical absorption of red and…
Nuclear & Particle PhysicsQ-Value
The net amount of energy released or absorbed during a nuclear reaction or radioactive decay process.
Nuclear & Particle PhysicsQuantum Chromodynamics (QCD)
The relativistic quantum field theory describing the strong nuclear interaction between color-charged quarks and gluons.
Condensed Matter & Materials PhysicsQuantum Confinement Effect
The shift and quantization of electronic energy levels when charge carriers are confined within spatial dimensions smaller than their De…
Quantum & Atomic PhysicsQuantum Decoherence
The loss of quantum coherence where interaction between a quantum system and its macro-environment converts a quantum superposition into a…
Quantum & Atomic PhysicsQuantum Dots
Nanometer-scale semiconductor crystals that trap charge carriers in all three spatial dimensions, exhibiting artificial atom quantized…
Quantum & Atomic PhysicsQuantum Electrodynamics (QED)
The relativistic quantum field theory describing how light (photons) and charged matter (electrons/positrons) interact.
Quantum & Atomic PhysicsQuantum Entanglement
A quantum phenomenon in which two or more particles become interconnected such that the quantum state of each particle cannot be described…