User:John R. Brews/Articles
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- Atomic units [r]: A system of units convenient for atomic and molecular calculations. [e]
- Centrifugal force [r]: A radially outward force experienced by an object moving in a curved path [e]
- Centripetal force [r]: The force directed normal to the path of a moving body that enables the body to navigate the curvature of the path [e]
- Clairaut's theorem [r]: A theorem describing the figure of the Earth as an oblate spheroid. [e]
- Comité International des Poids et Mesures [r]: An international committee set up to promote uniformity in units of measurement. [e]
- Coriolis effect [r]: A disorientation caused by misinterpretation of rotational signals by the ear, important particularly to astronauts and pilots. [e]
- Coriolis force [r]: An inertial force upon a moving object that is perpendicular to its velocity as that is seen from a rotating frame of reference, and also to the axis of rotation. [e]
- Doppler effect [r]: Frequency changes of a wave due to relative motion between source and observer. [e]
- Electronic band structure [r]: The very closely spaced energy levels available to electrons in solids, which are separated from each other by energy gaps. [e]
- Fermi function [r]: The equilibrium occupancy of an energy level in a system of independent fermions at a fixed temperature. [e]
- Foucault pendulum [r]: A pendulum demonstrating the Earth's rotation as it maintains its plane of motion independent of movement of its suspension attached to planet Earth. [e]
- Frame of reference (physics) [r]: An observational set of coordinates tied to the motion of an observer, used to describe physical events and possibly including a measurement apparatus. [e]
- Gyromagnetic ratio [r]: The constant of proportionality between the magnetic moment and angular momentum of an object. [e]
- Inertial forces [r]: Forces introduced to enable the use of the laws of motion in accelerating frames of reference, such as rotational frames [e]
- Inertial frame of reference [r]: A frame of reference in which the laws of physics take their simplest form. [e]
- Magnetic moment [r]: A vector property of an object that determines the torque it experiences in a magnetic flux density. [e]
- Magnetization [r]: Magnetic moment per unit volume of a material, denoted M, defined in terms of the magnetic moments of its constituents by M=(1/V)Σj mj where the magnetic moment mj of the j-th constituent in the volume V is a vector property that determines the torque the object experiences in a magnetic field tending to align its moment with the field. [e]
- Measurement in quantum mechanics [r]: The interpretation of measurement in quantum mechanics [e]
- Metre (unit) [r]: Unit of length; one of the seven SI base units. [e]
- MOS capacitor [r]: A two-terminal device consisting of three layers: a metal gate, a semiconducting body and a separating insulator, often an oxide. [e]
- MOSFET [r]: A type of field-effect transistor with four electrical contacts and three layers: a metal top layer (connected to the gate contact),separated by an insulating layer (usually an oxide layer) from a semiconductor layer (connected to the body contact). The gate voltage switches "on" and "off" the electrical connection between a source and drain contact at the semiconductor surface. [e]
- Relative permeability [r]: A factor describing magnetizability as a proportionality between magnetic flux density and magnetic field in a magnetic material or medium. [e]
- Rydberg constant [r]: A theoretical constant related to the spectrum of atomic hydrogen defined by the Bohr theory of the atom as: R∞ = mee4/(4πℏ3 c)·[μ0 c2/(4π)]2 . [e]
- Schottky diode [r]: A two-terminal electrical device consisting of conductive gate (for example, a metal) on top of a semiconductor body used for switching, rectification and photo-detection [e]
- Semiconductor diode [r]: Two-terminal device that conducts current in only one direction, made of two or more layers of material, of which at least one is a semiconductor. [e]
- Semiconductor [r]: A substance (usually a solid) with electrical conductivity intermediate between metals and insulators. [e]
- Speed of light [r]: A physical constant c describing the speed of electromagnetic radiation in vacuum. In the International System of Units the metre is the distance light travels in classical vacuum in 1/c seconds, using the defined value c = c0 ≡ 299 792 458 m/s (exact). [e]
- Vacuum (classical) [r]: The term classical vacuum as used in classical electromagnetism and in the definition of the SI units refers to an ideal reference medium devoid of all particles, with ideal properties. These ideal properties include: independence from field strengths, direction, frequency, or polarization, and from temperature. [e]
- Vacuum (partial) [r]: A realizable vacuum with a gaseous pressure that is much less than atmospheric. [e]
- Vacuum (quantum electrodynamic) [r]: The term quantum electrodynamic vacuum, or QED vacuum, refers to the ground state of the electromagnetic field, which is subject to fluctuations about a dormant zero average-field condition. [e]
- Rydberg constant [r]: A theoretical constant related to the spectrum of atomic hydrogen defined by the Bohr theory of the atom as: R∞ = mee4/(4πℏ3 c)·[μ0 c2/(4π)]2 . [e]
- Widlar current source [r]: a modification of the basic two-transistor current mirror that incorporates an emitter degeneration resistor for only the output transistor, enabling the current source to generate low currents using only moderate resistor values and therefore a small area [e]