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842 terms · page 9 of 36
Drag Force
The fluid resistance force opposing the motion of an object moving through a liquid or gas.
Astrophysics, Cosmology & RelativityDrake Equation
A probabilistic equation formulated by Frank Drake in 1961 to estimate the number N of active, communicative extraterrestrial civilizations…
Condensed Matter & Materials PhysicsDuctility
A material's mechanical capability to undergo significant plastic strain deformation under tensile stress before fracturing.
Plasma PhysicsDusty Plasma
A complex plasma containing solid nanometer-to-micrometer scale dust grains that collect high negative charges from surrounding plasma…
Classical MechanicsDynamic Equilibrium
The state of a physical system moving at constant linear velocity and constant angular velocity with zero net force and zero net torque.
Geophysics & Environmental PhysicsEarth's Energy Budget
The precise balance between incoming solar radiation absorbed by Earth and outgoing thermal infrared radiation emitted back into space.
Geophysics & Environmental PhysicsEarth's Inner Core
The solid, innermost spherical core of Earth composed primarily of a crystallized iron-nickel alloy at intense pressure.
Geophysics & Environmental PhysicsEarth's Outer Core
The fluid interior layer of Earth ~2,260 km thick composed of liquid iron-nickel alloy surrounding the solid inner core.
Waves, Oscillations & AcousticsEcho
A distinct reflected sound wave received at the listener's ear with sufficient time delay after the direct sound.
Electromagnetism & ElectronicsEddy Currents
Loops of electric current induced within solid bulk conductors by a changing magnetic field according to Faraday's law.
Plasma PhysicsEdge Localized Modes (ELMs)
Periodic magnetohydrodynamic bursts occurring at the boundary edge pedestal of H-mode tokamak plasmas, expelling heat and particles toward…
Biophysics & Medical PhysicsEffective Dose
A radiation protection quantity representing the overall stochastic health risk to the whole body by weighting organ equivalent doses by…
Condensed Matter & Materials PhysicsEffective Mass
A parameter that simplifies modeling electron and hole dynamics in a crystal lattice by treating them as free particles with a modified…
Classical MechanicsEfficiency
The ratio of useful work output to total energy input for a machine or system.
Mathematical & Computational PhysicsEigenvalue Problem
The linear algebra problem of finding non-zero eigenvectors v that, when operated on by a linear operator Â, yield a scalar multiple λ of…
Mathematical & Computational PhysicsEigenvalues and Eigenvectors
Special vectors v associated with a linear transformation matrix A that maintain their spatial direction when operated on, scaled only by…
Astrophysics, Cosmology & RelativityEinstein Field Equations
The set of 10 non-linear partial differential equations in general relativity relating spacetime curvature (Ricci tensor R_μν) to…
Classical MechanicsElastic Collision
A collision between bodies in which both total linear momentum and total kinetic energy are conserved.
Classical MechanicsElasticity
The mechanical property of a material to deform under applied stress and return to its original shape when stress is removed.
Electromagnetism & ElectronicsElectric Charge
A fundamental intrinsic physical property of subatomic particles that causes matter to experience an electrostatic force when placed in an…
Electromagnetism & ElectronicsElectric Current
The rate of net flow of electric charge through a cross-sectional area of a conductor per unit time.
Electromagnetism & ElectronicsElectric Dipole
A system of two equal and opposite electric charges (+q and -q) separated by a small distance d.
Electromagnetism & ElectronicsElectric Dipole Moment
A vector quantity measuring the strength and orientation of an electric dipole, pointing from the negative charge toward the positive…
Electromagnetism & ElectronicsElectric Field
A vector field surrounding an electric charge that exerts an electrostatic force on any other charge placed within the field.