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    Example and Directions
    Words (or words that have the same definition) The definition is case sensitive (Optional) Image to display with the definition [Not displayed in Glossary, only in pop-up on pages] (Optional) Caption for Image (Optional) External or Internal Link (Optional) Source for Definition
    (Eg. "Genetic, Hereditary, DNA ...") (Eg. "Relating to genes or heredity") The infamous double helix CC-BY-SA; Delmar Larsen
    Glossary Entries



    Image Caption Link Source
    absolute temperature scale scale, such as Kelvin, with a zero point that is absolute zero       OpenStax
    absolute zero temperature at which the average kinetic energy of molecules is zero       OpenStax
    AC current current that fluctuates sinusoidally with time at a fixed frequency       OpenStax
    AC voltage voltage that fluctuates sinusoidally with time at a fixed frequency       OpenStax
    adiabatic process process during which no heat is transferred to or from the system       OpenStax
    alternating current (ac) flow of electric charge that periodically reverses direction       OpenStax
    ammeter instrument that measures current       OpenStax
    ampere (amp) SI unit for current; \(\displaystyle 1A=1C/s\)       OpenStax
    Ampère’s law physical law that states that the line integral of the magnetic field around an electric current is proportional to the current       OpenStax
    area vector vector with magnitude equal to the area of a surface and direction perpendicular to the surface       OpenStax
    average power time average of the instantaneous power over one cycle       OpenStax
    Avogadro’s number \(N_A\), the number of molecules in one mole of a substance; \(N_A=6.02×10^{23}\) particles/mole       OpenStax
    back emf emf generated by a running motor, because it consists of a coil turning in a magnetic field; it opposes the voltage powering the motor       OpenStax
    bandwidth range of angular frequencies over which the average power is greater than one-half the maximum value of the average power       OpenStax
    Biot-Savart law an equation giving the magnetic field at a point produced by a current-carrying wire       OpenStax
    Boltzmann constant \(k_B\), a physical constant that relates energy to temperature and appears in the ideal gas law; \(k_B=1.38×10^{−23}J/K\)       OpenStax
    boundary imagined walls that separate the system and its surroundings       OpenStax
    calorie (cal) energy needed to change the temperature of 1.00 g of water by 1.00°C       OpenStax
    calorimeter container that prevents heat transfer in or out       OpenStax
    calorimetry study of heat transfer inside a container impervious to heat       OpenStax
    capacitance amount of charge stored per unit volt       OpenStax
    capacitive reactance opposition of a capacitor to a change in current       OpenStax
    capacitor device that stores electrical charge and electrical energy       OpenStax
    Carnot cycle cycle that consists of two isotherms at the temperatures of two reservoirs and two adiabatic processes connecting the isotherms       OpenStax
    Carnot engine Carnot heat engine, refrigerator, or heat pump that operates on a Carnot cycle       OpenStax
    Carnot principle principle governing the efficiency or performance of a heat device operating on a Carnot cycle: any reversible heat device working between two reservoirs must have the same efficiency or performance coefficient, greater than that of an irreversible heat device operating between the same two reservoirs       OpenStax
    Celsius scale temperature scale in which the freezing point of water is 0°C and the boiling point of water is 100°C       OpenStax
    charging by induction process by which an electrically charged object brought near a neutral object creates a charge separation in that object       OpenStax
    circuit complete path that an electrical current travels along       OpenStax
    Clausius statement of the second law of thermodynamics heat never flows spontaneously from a colder object to a hotter object       OpenStax
    closed system system that is mechanically and thermally isolated from its environment       OpenStax
    coefficient of linear expansion (\(α\)) material property that gives the change in length, per unit length, per \(1-°C\) change in temperature; a constant used in the calculation of linear expansion; the coefficient of linear expansion depends to some degree on the temperature of the material       OpenStax
    coefficient of performance measure of effectiveness of a refrigerator or heat pump       OpenStax
    coefficient of volume expansion (\(β\)) similar to αα but gives the change in volume, per unit volume, per \(1-°C\) change in temperature       OpenStax
    cold reservoir sink of heat used by a heat engine       OpenStax
    conduction heat transfer through stationary matter by physical contact       OpenStax
    conduction electron electron that is free to move away from its atomic orbit       OpenStax
    conductor material that allows electrons to move separately from their atomic orbits; object with properties that allow charges to move about freely within it       OpenStax
    continuous charge distribution total source charge composed of so large a number of elementary charges that it must be treated as continuous, rather than discrete       OpenStax
    convection heat transfer by the macroscopic movement of fluid       OpenStax
    conventional current current that flows through a circuit from the positive terminal of a battery through the circuit to the negative terminal of the battery       OpenStax
    cosmic rays comprised of particles that originate mainly from outside the solar system and reach Earth       OpenStax
    coulomb SI unit of electric charge       OpenStax
    Coulomb force another term for the electrostatic force       OpenStax
    Coulomb’s law mathematical equation calculating the electrostatic force vector between two charged particles       OpenStax
    critical point for a given substance, the combination of temperature and pressure above which the liquid and gas phases are indistinguishable       OpenStax
    critical pressure pressure at the critical point       OpenStax
    critical temperature temperature at the critical point       OpenStax
    critical temperature \(T_c\) at which the isotherm has a point with zero slope       OpenStax
    critical temperature temperature at which a material reaches superconductivity       OpenStax
    current density flow of charge through a cross-sectional area divided by the area       OpenStax
    cyclic process process in which the state of the system at the end is same as the state at the beginning       OpenStax
    cyclotron device used to accelerate charged particles to large kinetic energies       OpenStax
    cylindrical symmetry system only varies with distance from the axis, not direction       OpenStax
    Dalton’s law of partial pressures physical law that states that the total pressure of a gas is the sum of partial pressures of the component gases       OpenStax
    dees large metal containers used in cyclotrons that serve contain a stream of charged particles as their speed is increased       OpenStax
    degree Celsius (°C) unit on the Celsius temperature scale       OpenStax
    degree Fahrenheit (°F) unit on the Fahrenheit temperature scale       OpenStax

    degree of freedom

    independent kind of motion possessing energy, such as the kinetic energy of motion in one of the three orthogonal spatial directions       OpenStax
    diamagnetic materials their magnetic dipoles align oppositely to an applied magnetic field; when the field is removed, the material is unmagnetized       OpenStax
    dielectric insulating material used to fill the space between two plates       OpenStax
    dielectric breakdown phenomenon that occurs when an insulator becomes a conductor in a strong electrical field       OpenStax
    dielectric constant factor by which capacitance increases when a dielectric is inserted between the plates of a capacitor       OpenStax
    dielectric strength critical electrical field strength above which molecules in insulator begin to break down and the insulator starts to conduct       OpenStax
    diode nonohmic circuit device that allows current flow in only one direction       OpenStax
    dipole two equal and opposite charges that are fixed close to each other       OpenStax
    dipole moment property of a dipole; it characterizes the combination of distance between the opposite charges, and the magnitude of the charges       OpenStax
    direct current (dc) flow of electric charge in only one direction       OpenStax
    disorder measure of order in a system; the greater the disorder is, the higher the entropy       OpenStax
    displacement current extra term in Maxwell’s equations that is analogous to a real current but accounts for a changing electric field producing a magnetic field, even when the real current is present       OpenStax
    drift velocity velocity of a charge as it moves nearly randomly through a conductor, experiencing multiple collisions, averaged over a length of a conductor, whose magnitude is the length of conductor traveled divided by the time it takes for the charges to travel the length       OpenStax
    eddy current current loop in a conductor caused by motional emf       OpenStax
    efficiency (e) output work from the engine over the input heat to the engine from the hot reservoir       OpenStax
    electric charge physical property of an object that causes it to be attracted toward or repelled from another charged object; each charged object generates and is influenced by a force called an electric force       OpenStax
    electric dipole system of two equal but opposite charges a fixed distance apart       OpenStax
    electric dipole moment quantity defined as \(\displaystyle \{vec{p}=q\vec{d}\) for all dipoles, where the vector points from the negative to positive charge       OpenStax
    electric field physical phenomenon created by a charge; it “transmits” a force between a two charges       OpenStax
    electric flux dot product of the electric field and the area through which it is passing       OpenStax
    electric force noncontact force observed between electrically charged objects       OpenStax
    electric generator device for converting mechanical work into electric energy; it induces an emf by rotating a coil in a magnetic field       OpenStax
    electric potential potential energy per unit charge       OpenStax
    electric potential difference the change in potential energy of a charge q moved between two points, divided by the charge.       OpenStax
    electric potential energy potential energy stored in a system of charged objects due to the charges       OpenStax
    electrical conductivity measure of a material’s ability to conduct or transmit electricity       OpenStax
    electrical current rate at which charge flows, \(\displaystyle I=\frac{dQ}{dt}\)       OpenStax
    electrical power time rate of change of energy in an electric circuit       OpenStax
    electromotive force (emf) energy produced per unit charge, drawn from a source that produces an electrical current       OpenStax
    electron particle surrounding the nucleus of an atom and carrying the smallest unit of negative charge       OpenStax
    electron-volt energy given to a fundamental charge accelerated through a potential difference of one volt       OpenStax
    electrostatic attraction phenomenon of two objects with opposite charges attracting each other       OpenStax
    electrostatic force amount and direction of attraction or repulsion between two charged bodies; the assumption is that the source charges have no acceleration       OpenStax
    electrostatic precipitators filters that apply charges to particles in the air, then attract those charges to a filter, removing them from the airstream       OpenStax
    electrostatic repulsion phenomenon of two objects with like charges repelling each other       OpenStax
    electrostatics study of charged objects which are not in motion       OpenStax
    emissivity measure of how well an object radiates       OpenStax
    energy density energy stored in a capacitor divided by the volume between the plates       OpenStax
    entropy state function of the system that changes when heat is transferred between the system and the environment       OpenStax
    entropy statement of the second law of thermodynamics entropy of a closed system or the entire universe never decreases       OpenStax
    environment outside of the system being studied       OpenStax
    equation of state describes properties of matter under given physical conditions       OpenStax
    equilibrium thermal balance established between two objects or parts within a system       OpenStax
    equipartition theorem theorem that the energy of a classical thermodynamic system is shared equally among its degrees of freedom       OpenStax
    equipotential line two-dimensional representation of an equipotential surface       OpenStax
    equipotential surface surface (usually in three dimensions) on which all points are at the same potential       OpenStax
    equivalent resistance resistance of a combination of resistors; it can be thought of as the resistance of a single resistor that can replace a combination of resistors in a series and/or parallel circuit       OpenStax
    extensive variable variable that is proportional to the amount of matter in the system       OpenStax
    Fahrenheit scale temperature scale in which the freezing point of water is 32°F and the boiling point of water is 212°F       OpenStax
    Faraday’s law induced emf is created in a closed loop due to a change in magnetic flux through the loop       OpenStax
    ferromagnetic materials contain groups of dipoles, called domains, that align with the applied magnetic field; when this field is removed, the material is still magnetized       OpenStax
    field line smooth, usually curved line that indicates the direction of the electric field       OpenStax
    field line density number of field lines per square meter passing through an imaginary area; its purpose is to indicate the field strength at different points in space       OpenStax
    first law of thermodynamics the change in internal energy for any transition between two equilibrium states is \(ΔE_{int}=Q−W\)       OpenStax
    flux quantity of something passing through a given area       OpenStax
    free electrons also called conduction electrons, these are the electrons in a conductor that are not bound to any particular atom, and hence are free to move around       OpenStax
    gamma ray (\(\displaystyle γ\) ray) extremely high frequency electromagnetic radiation emitted by the nucleus of an atom, either from natural nuclear decay or induced nuclear processes in nuclear reactors and weapons; the lower end of the \(\displaystyle γ\) -ray frequency range overlaps the upper end of the X-ray range, but \(\displaystyle γ\) rays can have the highest frequency of any electromagnetic radiation       OpenStax
    gauss G, unit of the magnetic field strength; \(\displaystyle 1G=10^{−4}T\)       OpenStax
    Gaussian surface any enclosed (usually imaginary) surface       OpenStax
    greenhouse effect warming of the earth that is due to gases such as carbon dioxide and methane that absorb infrared radiation from Earth’s surface and reradiate it in all directions, thus sending some of it back toward Earth       OpenStax
    grounding process of attaching a conductor to the earth to ensure that there is no potential difference between it and Earth       OpenStax
    Hall effect creation of voltage across a current-carrying conductor by a magnetic field       OpenStax
    heat energy transferred solely due to a temperature difference       OpenStax
    heat engine device that converts heat into work       OpenStax
    heat of fusion energy per unit mass required to change a substance from the solid phase to the liquid phase, or released when the substance changes from liquid to solid       OpenStax
    heat of sublimation energy per unit mass required to change a substance from the solid phase to the vapor phase       OpenStax
    heat of vaporization energy per unit mass required to change a substance from the liquid phase to the vapor phase       OpenStax
    heat pump device that delivers heat to a hot reservoir       OpenStax
    heat transfer movement of energy from one place or material to another as a result of a difference in temperature       OpenStax
    helical motion superposition of circular motion with a straight-line motion that is followed by a charged particle moving in a region of magnetic field at an angle to the field       OpenStax
    henry (H) unit of inductance, \(\displaystyle 1H=1Ω⋅s\); it is also expressed as a volt second per ampere       OpenStax
    hot reservoir source of heat used by a heat engine       OpenStax
    hysteresis property of ferromagnets that is seen when a material’s magnetic field is examined versus the applied magnetic field; a loop is created resulting from sweeping the applied field forward and reverse       OpenStax
    ideal gas gas at the limit of low density and high temperature       OpenStax
    ideal gas law physical law that relates the pressure and volume of a gas, far from liquefaction, to the number of gas molecules or number of moles of gas and the temperature of the gas       OpenStax
    impedance ac analog to resistance in a dc circuit, which measures the combined effect of resistance, capacitive reactance, and inductive reactance       OpenStax
    induced dipole typically an atom, or a spherically symmetric molecule; a dipole created due to opposite forces displacing the positive and negative charges       OpenStax
    induced electric field created based on the changing magnetic flux with time       OpenStax
    induced electric-dipole moment dipole moment that a nonpolar molecule may acquire when it is placed in an electrical field       OpenStax
    induced electrical field electrical field in the dielectric due to the presence of induced charges       OpenStax
    induced emf short-lived voltage generated by a conductor or coil moving in a magnetic field       OpenStax
    induced surface charges charges that occur on a dielectric surface due to its polarization       OpenStax
    inductance property of a device that tells how effectively it induces an emf in another device       OpenStax
    inductive reactance opposition of an inductor to a change in current       OpenStax
    inductive time constant denoted by τ, the characteristic time given by quantity L/R of a particular series RL circuit       OpenStax
    inductor part of an electrical circuit to provide self-inductance, which is symbolized by a coil of wire       OpenStax
    infinite straight wire straight wire whose length is much, much greater than either of its other dimensions, and also much, much greater than the distance at which the field is to be calculated       OpenStax
    infrared radiation region of the electromagnetic spectrum with a frequency range that extends from just below the red region of the visible light spectrum up to the microwave region, or from \(\displaystyle 0.74μm\) to \(\displaystyle 300μm\)       OpenStax
    ink jet printer small ink droplets sprayed with an electric charge are controlled by electrostatic plates to create images on paper       OpenStax
    insulator material that holds electrons securely within their atomic orbits       OpenStax
    intensive variable variable that is independent of the amount of matter in the system       OpenStax
    internal energy average of the total mechanical energy of all the molecules or entities in the system       OpenStax
    internal energy sum of the mechanical energies of all of the molecules in it       OpenStax
    internal resistance amount of resistance to the flow of current within the voltage source       OpenStax
    ion atom or molecule with more or fewer electrons than protons       OpenStax
    irreversibility phenomenon associated with a natural process       OpenStax
    irreversible process process in which neither the system nor its environment can be restored to their original states at the same time       OpenStax
    isentropic reversible adiabatic process where the process is frictionless and no heat is transferred       OpenStax
    isobaric process process during which the system’s pressure does not change       OpenStax
    isochoric process process during which the system’s volume does not change       OpenStax
    isothermal process process during which the system’s temperature remains constant       OpenStax
    Josephson junction junction of two pieces of superconducting material separated by a thin layer of insulating material, which can carry a supercurrent       OpenStax
    junction rule sum of all currents entering a junction must equal the sum of all currents leaving the junction       OpenStax
    Kelvin scale (K) temperature scale in which 0 K is the lowest possible temperature, representing absolute zero       OpenStax
    Kelvin statement of the second law of thermodynamics it is impossible to convert the heat from a single source into work without any other effect       OpenStax
    kilocalorie (kcal) energy needed to change the temperature of 1.00 kg of water between 14.5°C and 15.5°C       OpenStax
    kinetic theory of gases theory that derives the macroscopic properties of gases from the motion of the molecules they consist of       OpenStax
    Kirchhoff’s rules set of two rules governing current and changes in potential in an electric circuit       OpenStax
    latent heat coefficient general term for the heats of fusion, vaporization, and sublimation       OpenStax
    law of conservation of charge net electric charge of a closed system is constant       OpenStax
    LC circuit circuit composed of an ac source, inductor, and capacitor       OpenStax
    Lenz’s law direction of an induced emf opposes the change in magnetic flux that produced it; this is the negative sign in Faraday’s law       OpenStax
    linear charge density amount of charge in an element of a charge distribution that is essentially one-dimensional (the width and height are much, much smaller than its length); its units are C/m       OpenStax
    loop rule algebraic sum of changes in potential around any closed circuit path (loop) must be zero       OpenStax
    magnetic damping drag produced by eddy currents       OpenStax
    magnetic dipole closed-current loop       OpenStax
    magnetic dipole moment term IA of the magnetic dipole, also called \(\displaystyle μ\)       OpenStax
    magnetic domains groups of magnetic dipoles that are all aligned in the same direction and are coupled together quantum mechanically       OpenStax
    magnetic energy density energy stored per volume in a magnetic field       OpenStax
    magnetic field lines continuous curves that show the direction of a magnetic field; these lines point in the same direction as a compass points, toward the magnetic south pole of a bar magnet       OpenStax
    magnetic flux measurement of the amount of magnetic field lines through a given area       OpenStax
    magnetic force force applied to a charged particle moving through a magnetic field       OpenStax
    magnetic susceptibility ratio of the magnetic field in the material over the applied field at that time; positive susceptibilities are either paramagnetic or ferromagnetic (aligned with the field) and negative susceptibilities are diamagnetic (aligned oppositely with the field)       OpenStax
    mass spectrometer device that separates ions according to their charge-to-mass ratios       OpenStax
    Maxwell-Boltzmann distribution function that can be integrated to give the probability of finding ideal gas molecules with speeds in the range between the limits of integration       OpenStax
    Maxwell’s equations set of four equations that comprise a complete, overarching theory of electromagnetism       OpenStax
    mean free path average distance between collisions of a particle       OpenStax
    mean free time average time between collisions of a particle       OpenStax
    mechanical equivalent of heat work needed to produce the same effects as heat transfer       OpenStax
    Meissner effect phenomenon that occurs in a superconducting material where all magnetic fields are expelled       OpenStax
    microwaves electromagnetic waves with wavelengths in the range from 1 mm to 1 m; they can be produced by currents in macroscopic circuits and devices       OpenStax
    molar heat capacity at constant pressure quantifies the ratio of the amount of heat added removed to the temperature while measuring at constant pressure       OpenStax
    molar heat capacity at constant volume quantifies the ratio of the amount of heat added removed to the temperature while measuring at constant volume       OpenStax
    mole quantity of a substance whose mass (in grams) is equal to its molecular mass       OpenStax
    most probable speed speed near which the speeds of most molecules are found, the peak of the speed distribution function       OpenStax
    motionally induced emf voltage produced by the movement of a conducting wire in a magnetic field       OpenStax
    motor (dc) loop of wire in a magnetic field; when current is passed through the loops, the magnetic field exerts torque on the loops, which rotates a shaft; electrical energy is converted into mechanical work in the process       OpenStax
    mutual inductance geometric quantity that expresses how effective two devices are at inducing emfs in one another       OpenStax
    net rate of heat transfer by radiation \(P_{net}=σeA(T_2^4−T_1^4)\)       OpenStax
    neutron neutral particle in the nucleus of an atom, with (nearly) the same mass as a proton       OpenStax
    nonohmic type of a material for which Ohm’s law is not valid       OpenStax
    north magnetic pole currently where a compass points to north, near the geographic North Pole; this is the effective south pole of a bar magnet but has flipped between the effective north and south poles of a bar magnet multiple times over the age of Earth       OpenStax
    ohm (\(\displaystyle Ω\)) unit of electrical resistance, \(\displaystyle 1Ω=1V/A\)       OpenStax
    Ohm’s law empirical relation stating that the current I is proportional to the potential difference V; it is often written as \(\displaystyle V=IR\), where R is the resistance       OpenStax
    ohmic type of a material for which Ohm’s law is valid, that is, the voltage drop across the device is equal to the current times the resistance       OpenStax
    open system system that can exchange energy and/or matter with its surroundings       OpenStax
    parallel combination components in a circuit arranged with one side of each component connected to one side of the circuit and the other sides of the components connected to the other side of the circuit       OpenStax
    parallel-plate capacitor system of two identical parallel conducting plates separated by a distance       OpenStax
    paramagnetic materials their magnetic dipoles align partially in the same direction as the applied magnetic field; when this field is removed, the material is unmagnetized       OpenStax
    partial pressure pressure a gas would create if it occupied the total volume of space available       OpenStax
    peak emf maximum emf produced by a generator       OpenStax
    peak speed same as “most probable speed”       OpenStax
    perfect engine engine that can convert heat into work with 100%100% efficiency       OpenStax
    perfect refrigerator (heat pump) refrigerator (heat pump) that can remove (dump) heat without any input of work       OpenStax
    permanent dipole typically a molecule; a dipole created by the arrangement of the charged particles from which the dipole is created       OpenStax
    permeability of free space \(\displaystyle μ_0\), measure of the ability of a material, in this case free space, to support a magnetic field       OpenStax
    permittivity of vacuum also called the permittivity of free space, and constant describing the strength of the electric force in a vacuum       OpenStax
    phase angle amount by which the voltage and current are out of phase with each other in a circuit       OpenStax
    phase diagram graph of pressure vs. temperature of a particular substance, showing at which pressures and temperatures the phases of the substance occur       OpenStax
    photoconductor substance that is an insulator until it is exposed to light, when it becomes a conductor       OpenStax
    planar symmetry system only varies with distance from a plane       OpenStax
    polarization slight shifting of positive and negative charges to opposite sides of an object       OpenStax
    potential difference difference in electric potential between two points in an electric circuit, measured in volts       OpenStax
    potential drop loss of electric potential energy as a current travels across a resistor, wire, or other component       OpenStax
    power factor amount by which the power delivered in the circuit is less than the theoretical maximum of the circuit due to voltage and current being out of phase       OpenStax
    Poynting vector vector equal to the cross product of the electric-and magnetic fields, that describes the flow of electromagnetic energy through a surface       OpenStax
    principle of superposition useful fact that we can simply add up all of the forces due to charges acting on an object       OpenStax
    proton particle in the nucleus of an atom and carrying a positive charge equal in magnitude to the amount of negative charge carried by an electron       OpenStax
    pV diagram graph of pressure vs. volume       OpenStax
    quality factor dimensionless quantity that describes the sharpness of the peak of the bandwidth; a high quality factor is a sharp or narrow resonance peak       OpenStax
    quasi-static process evolution of a system that goes so slowly that the system involved is always in thermodynamic equilibrium       OpenStax
    radar common application of microwaves; radar can determine the distance to objects as diverse as clouds and aircraft, as well as determine the speed of a car or the intensity of a rainstorm       OpenStax
    radiation energy transferred by electromagnetic waves directly as a result of a temperature difference       OpenStax
    radiation pressure force divided by area applied by an electromagnetic wave on a surface       OpenStax
    radio waves electromagnetic waves with wavelengths in the range from 1 mm to 100 km; they are produced by currents in wires and circuits and by astronomical phenomena       OpenStax
    rate of conductive heat transfer rate of heat transfer from one material to another       OpenStax
    RC circuit circuit that contains both a resistor and a capacitor       OpenStax
    refrigerator device that removes heat from a cold reservoir       OpenStax
    resistance electric property that impedes current; for ohmic materials, it is the ratio of voltage to current, \(\displaystyle R=V/I\)       OpenStax
    resistivity intrinsic property of a material, independent of its shape or size, directly proportional to the resistance, denoted by \(\displaystyle ρ\)       OpenStax
    resonant frequency frequency at which the amplitude of the current is a maximum and the circuit would oscillate if not driven by a voltage source       OpenStax
    reversible process process that can be reverted to restore both the system and its environment back to their original states together       OpenStax
    reversible process process in which both the system and the external environment theoretically can be returned to their original states       OpenStax
    right-hand rule-1 using your right hand to determine the direction of either the magnetic force, velocity of a charged particle, or magnetic field       OpenStax
    RL circuit A circuit with resistance and self-inductance       OpenStax
    RLC circuit circuit with an ac source, resistor, inductor, and capacitor all in series.       OpenStax
    rms current root mean square of the current       OpenStax
    rms voltage root mean square of the voltage       OpenStax
    root-mean-square (rms) speed square root of the average of the square (of a quantity)       OpenStax
    schematic graphical representation of a circuit using standardized symbols for components and solid lines for the wire connecting the components       OpenStax
    self-inductance effect of the device inducing emf in itself       OpenStax
    series combination components in a circuit arranged in a row one after the other in a circuit       OpenStax
    shock hazard hazard in which an electric current passes through a person       OpenStax
    solenoid thin wire wound into a coil that produces a magnetic field when an electric current is passed through it       OpenStax
    south magnetic pole currently where a compass points to the south, near the geographic South Pole; this is the effective north pole of a bar magnet but has flipped just like the north magnetic pole       OpenStax
    specific heat amount of heat necessary to change the temperature of 1.00 kg of a substance by 1.00°C; also called “specific heat capacity”       OpenStax
    spherical symmetry system only varies with the distance from the origin, not in direction       OpenStax
    SQUID (Superconducting Quantum Interference Device) device that is a very sensitive magnetometer, used to measure extremely subtle magnetic fields       OpenStax
    static electricity buildup of electric charge on the surface of an object; the arrangement of the charge remains constant (“static”)       OpenStax
    Stefan-Boltzmann law of radiation \(P=σAeT^4\), where \(σ=5.67×10^{−8}J/s⋅m^2⋅K^4\) is the Stefan-Boltzmann constant, A is the surface area of the object, T is the absolute temperature, and e is the emissivity       OpenStax
    step-down transformer transformer that decreases voltage and increases current       OpenStax
    step-up transformer transformer that increases voltage and decreases current       OpenStax
    sublimation phase change from solid to gas       OpenStax
    superconductivity phenomenon that occurs in some materials where the resistance goes to exactly zero and all magnetic fields are expelled, which occurs dramatically at some low critical temperature \(\displaystyle (T_C)\)       OpenStax
    supercritical condition of a fluid being at such a high temperature and pressure that the liquid phase cannot exist       OpenStax
    superposition concept that states that the net electric field of multiple source charges is the vector sum of the field of each source charge calculated individually       OpenStax
    surface charge density amount of charge in an element of a two-dimensional charge distribution (the thickness is small); its units are \(\displaystyle C/m^2\)       OpenStax
    surroundings environment that interacts with an open system       OpenStax
    temperature quantity measured by a thermometer, which reflects the mechanical energy of molecules in a system       OpenStax
    terminal voltage potential difference measured across the terminals of a source when there is no load attached       OpenStax
    tesla SI unit for magnetic field: \(\displaystyle 1 T = 1 N/A-m\)       OpenStax
    thermal agitation thermal motion of atoms and molecules in any object at a temperature above absolute zero, which causes them to emit and absorb radiation       OpenStax
    thermal conductivity property of a material describing its ability to conduct heat       OpenStax
    thermal equilibrium condition in which heat no longer flows between two objects that are in contact; the two objects have the same temperature       OpenStax
    thermal expansion change in size or volume of an object with change in temperature       OpenStax
    thermal hazard hazard in which an excessive electric current causes undesired thermal effects       OpenStax
    thermal stress stress caused by thermal expansion or contraction       OpenStax
    thermodynamic process manner in which a state of a system can change from initial state to final state       OpenStax
    thermodynamic system object and focus of thermodynamic study       OpenStax
    third law of thermodynamics absolute zero temperature cannot be reached through any finite number of cooling steps       OpenStax
    three-wire system wiring system used at present for safety reasons, with live, neutral, and ground wires       OpenStax
    toroid donut-shaped coil closely wound around that is one continuous wire       OpenStax
    transformer device that transforms voltages from one value to another using induction       OpenStax
    transformer equation equation showing that the ratio of the secondary to primary voltages in a transformer equals the ratio of the number of turns in their windings       OpenStax
    triple point pressure and temperature at which a substance exists in equilibrium as a solid, liquid, and gas       OpenStax
    ultraviolet radiation electromagnetic radiation in the range extending upward in frequency from violet light and overlapping with the lowest X-ray frequencies, with wavelengths from 400 nm down to about 10 nm       OpenStax
    universal gas constant R, the constant that appears in the ideal gas law expressed in terms of moles, given by \(R=N_Ak_B\)       OpenStax
    Van de Graaff generator machine that produces a large amount of excess charge, used for experiments with high voltage       OpenStax
    van der Waals equation of state equation, typically approximate, which relates the pressure and volume of a gas to the number of gas molecules or number of moles of gas and the temperature of the gas       OpenStax
    vapor gas at a temperature below the boiling temperature       OpenStax
    vapor pressure pressure at which a gas coexists with its solid or liquid phase       OpenStax
    vapor pressure partial pressure of a vapor at which it is in equilibrium with the liquid (or solid, in the case of sublimation) phase of the same substance       OpenStax
    velocity selector apparatus where the crossed electric and magnetic fields produce equal and opposite forces on a charged particle moving with a specific velocity; this particle moves through the velocity selector not affected by either field while particles moving with different velocities are deflected by the apparatus       OpenStax
    visible light narrow segment of the electromagnetic spectrum to which the normal human eye responds, from about 400 to 750 nm       OpenStax
    voltage change in potential energy of a charge moved from one point to another, divided by the charge; units of potential difference are joules per coulomb, known as volt       OpenStax
    voltmeter instrument that measures voltage       OpenStax
    volume charge density amount of charge in an element of a three-dimensional charge distribution; its units are \(\displaystyle C/m^3\)       OpenStax
    X-ray invisible, penetrating form of very high frequency electromagnetic radiation, overlapping both the ultraviolet range and the \(\displaystyle γ\)-ray range       OpenStax
    xerography dry copying process based on electrostatics       OpenStax
    zeroth law of thermodynamics law that states that if two objects are in thermal equilibrium, and a third object is in thermal equilibrium with one of those objects, it is also in thermal equilibrium with the other object       OpenStax
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