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Vocabulary
Vocab Ch. 1-10 * Vocab Ch. 11-20 * Vocab Ch. 21-31
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Capacitance
capacitance (21.2): The ratio of an object's stored charge to its potential difference; measured in farads.
Capacitor
capacitor (21.2): A device with a specific capacitance that is used in electrical circuits to store charge.
electric field
electric field (21.1): A vector quantity that relates the force exerted on a charge to the size of the charge.
electric field line
electric field lines (21.1): The lines providing a picture of the electric field, showing direction and strength.
electric potential difference
electric potential difference (21.2): In an electric field, the change in potential energy per unit charge.
equipotential
equipotential (21.2): The potential difference of zero between two or more positions in an electric field.
Grounding
grounding (21 2) Removing excess charge from a charged body by connecting It to Earth.
volt
volt (21.2): Electric potential difference measured in joules per coulomb.
Ampere
ampere (A) (22.1): The base SI unit of current; one coulomb per second
battery
battery (22.1): A group of several voltaic or galvanic cells connected together to convert chemical energy to electrical energy.
conventional current
conventional current (22.1): The flow of positive charges.
electric current
electric current (22.1): The flow of charged particles.
kilowatt-hour
kilowatt-hour (kWh) (22.2): Energy unit; the amount of energy equal to 1000 watts delivered continuously for one hour (3600 seconds).
parallel connection
parallel connection (22.1): The arrangement of electric devices in a circuit where there is more than one current path.
photovoltaic cell
photovoltaic cell (22.1): A solar cell that changes light energy into electric energy.
Potentiometer
potentiometer (22.1): A variable resistor that allows continuous, rather than step-by-step, changes in current in an electric circuit; also called a rheostat.
Resistance
resistance (22.1): The ratio of the voltage across a device to the current through it.
Resistor
resistors (22.1): Devices with a specific resistance.
Schematic
schematic (22.1): A diagram of an electric circuit that uses
standard symbols for circuit elements.
series connection
series connection (22.1): The connection of electric devices in a circuit where there is only one current path.
Ammeter
ammeter (23.2): A device that measures current.
circuit breaker
circuit breaker (23.2): An automatic switch that opens, stopping all current, when the circuit is overloaded.
combination series-parallel circuit
combination series-parallel circuit (23.2): A complex circuit that it a combination of series and parallel branches.
equivalent resistance
equivalent resistance (23.1): In a series circuit, the sum of individual resistances.
Fuse
fuse (23.2): A short piece of metal that will melt, or blow, if too large a current passes through it and that acts as a safety device by stopping current to the entire circuit.
ground-fault interrupter
ground-fault Interrupter (23.2): A device containing an electronic circuit that detects current differences caused by an extra current path it opens the circuit and prevents electric shocks.
parallel circuit
parallel circuit (23.1): A circuit with several current paths, whose total current equals the sum of the currents in its branches.
series circuit
series circuit (23.1): A circuit in which current passes through each device, one after another.
short circuit
short circuit (23.2): Low-resistance connection between two points.
voltage divider
voltage divider (23.1): A series circuit used to produce a voltage source from a higher-voltage battery.
voltmeter
voltmeter (23.2): A device that measures voltage.
Armature
armature (24.2): A loop of wire in an electric motor that is mounted on a shaft or axle.
Domain
domain (24.1): A small group, usually 10 to 1000 microns, that is formed when the magnetic fields of the electrons in a group of neighboring atoms combine together.
electric motor
electric motor (24.2): A device that converts electrical energy to kinetic energy.
Electromagnet
electromagnet (24.1): A current-carrying coil with a north and south pole that is itself a magnet.
first right hand rule
first right-hand rule (24.1): The method used to determine the direction of the magnetic field around a current-carrying wire.
galvanometer
galvanometer (24 2) A device used to measure very small currents
magnetic field
magnetic field (24.1): A vector quantity that relates the force exerted on a magnet or current-carrying wire to the strength of the magnet or the size of the current.
magnetic flux
magnetic flux (24.1): The number of magnetic field lines that pass through a surface.
Polarized
polarized (16.2): Light consisting of waves that vibrate on a specific plane. (24.1): The quality of having two opposite magnetic poles, one south-seeking and one north-seeking.
second right hand rule
second right-hand rule (24.1): The method used to determine the direction of the field produced by an electromagnet.
Solenoid
solenoid (24.1): A coil of wire with many loops that acts like a magnet when a current is allowed to flow through it.
third right hand rule
third right-hand rule (24.2): The method used to determine the direction of the force on a current-carrying wire in a magnetic field.
eddy current
eddy currents (25.2): Currents that produce a magnetic field that opposes the motion that caused the currents. They are generated when a piece of metal moves through a magnetic field or when a metal loop is placed in a changing magnetic field.
electric generator
electric generator (25.1): A device that converts mechanical energy to electrical energy.
electromagnetic induction
electromagnetic induction (25.1): The generation of current through a circuit due to the relative motion between a wire and a magnetic field.
electromotive force
electromotive force (EMF) (25.1): The potential difference that is produced by electromagnetic induction.
Lenzs law
Lenz's law (25.2): The magnetic field resulting from induced current opposes the change in the field that caused the induced current.
mutual inductance
mutual inductance (25.2): Effect that occurs in a transformer when a varying magnetic field created in the primary coil is carried through the iron core to the secondary coil, where the varying field induces a varying EMF.
primary coil
primary coil (25.2): An insulated transformer coil that creates a varying magnetic field when it is connected to an alternating-current (AC) voltage source.
secondary coil
secondary coil (25.2): An insulated transformer coil in which varying EMF is induced.
self-inductance
Self-lnductance (25.2): The induction of EMF in a wire carrying a changing current.
step-down transformer
step-down transformer (25.2): A transformer in which the output voltage is smaller than the input voltage.
step-up transformer
step-up transformer (25.2): A transformer in which the output voltage is larger than the input voltage.
Transformer
transformer (25.2): A device used to increase or decrease AC voltages with little loss of energy.
Antenna
antenna (26.2): A device, usually a wire or rod, that generates electromagnetic waves when connected to an alternating current (AC) source.
electromagnetic radiation
electromagnetic radiation (26.2): Energy carried through space in the form of electromagnetic waves.
electromagnetic wave
electromagnetic wave (26.2): A wave consisting of coupled changing magnetic and electric fields that moves through space at the speed of light.
Isotope
isotopes (26 1) Atomic nuclei having the same number of protons but different numbers of neutrons.
mass spectrometer
mass spectrometer (26.1): A device that uses both magnetic and electric fields to precisely measure the masses of ionized atoms and molecules.
piezoelectricity
piezoelectricity (26.2): Property of quartz crystals, which, when bent or deformed by an applied voltage, will vibrate at a specific frequency and generate an EMF.
Receiver
receiver (26.2): A device used for reception of electromagnetic waves.
X ray
X ray (26.2) High frequency, short wave length electromagnetic waves.
Compton effect
Compton effect (27.1): The shift in the energy of scattered photons.
de Broglie wavelength
de Brogue wavelength (27.2): The length of de Broglie wave of a particle.
Heisenberg uncertainty principle
Heisenberg uncertainty principle (27.2): It is not possible to precisely measure both the position and momentum of a particle of light or matter at the same time.
photoelectric effect
photoelectric effect (27.1): The emission of electrons produced when electromagnetic radiation falls on certain metals.
Photon
photon (27.1): A light quantum that is massless, has energy and momentum, and travels at the speed of light.
Quantized
quantized (27.1): Small but measurable increments.
threshold frequency
threshold frequency (27.1): The certain minimum frequency at which radiation causes the ejection of electrons from a metal.
work function
work function (27.1): The energy with which electrons are held inside a metal.
absorption spectrum
absorption spectrum (28.1): A characteristic set of light wavelengths absorbed by a material, which can be used to indicate the composition of the material.
alpha particle
alpha (a) particle (28.1): Positively-charged particles consisting of two protons and two neutrons emitted by radioactive materials.
bohr model
Bohr model (28.1): A model of an atom with a central nucleus and electrons in specific quantized energy levels from which they can make transitions, emitting or absorbing electromagnetic radiation.
coherent light
coherent light (28.2): Light with the minima and maxima of the waves coinciding (in step).
electron cloud
electron cloud (28.2): The region in which there is a high probability of finding an electron.
emission spectrum
emission spectrum (28.1): The characteristic set of light wavelengths emitted by an atom.
energy level
energy level (28.1): The quantized amount of energy that an electron may have.
excited state
excited state (28.1): A higher energy level reached by an electron when it absorbs energy.
ground state
ground state (28.1): The lowest energy level occupied by an electron.
incoherent light
incoherent light (28.2): Light with the minima and maxima of the waves not necessarily coinciding.
Laser
laser (28 2): A device that generates coherent, directional, monochromatic light.
nuclear model
nuclear model (28.1): An atom is mostly empty space with a tiny, massive positively-charged central nucleus.
quantum mechanics
quantum mechanics (28.2): The study of the properties of matter using its wave properties.
quantum model
quantum model (28.2): A model that predicts only the probability that an electron is at a specific location.
quantum number
quantum number (28.1): The integer ratio of energy to its quantum increment.
Scintillation
scintillation (28.1): The small flash of light emitted when a substance is struck by a radioactive particle.
Spectroscope
spectroscope (28.1): Instrument used to study spectra.
Spectroscopy
spectroscopy (28.1): The study of spectra.
stimulated emission
stimulated emission (28.2): Process that occurs when an excited atom is struck by a photon and releases a photon of equal energy.
band theory
band theory (29.1): The theory that electrical conduction in solids can be explained in terms of energy bands and forbidden gaps.
conduction band
conduction band (29.1): In the atom of a solid, the lowest band that is not filled to capacity with electrons.
depletion layer
depletion layer (29.2): In a pn-junction diode, the area that is lacking charge carriers and thus is a poor conductor of electricity.
Diode
diode (29.2): Semiconductor device used to produce current in only one direction.
Dopant
dopant (29.1): An impurity atom that increases the conductivity of a semiconductor by adding either holes or electrons.
extrinsic semiconductor
extrinsic semiconductor (29.1): A semiconductor with greatly enhanced conductivity due to the addition of impurity atoms (dopants).
forbidden gap
forbidden gap (29.1): The region that separates bands of energy levels in solids by values of energy that no electrons possess.
Hole
hole (29.1): Absence of an electron in a semiconductor.
intrinsic semiconductor
intrinsic semiconductor (29.1): A pure semiconductor that carries charge as a result of thermally freed electrons and holes.
n-type semiconductor
n-type semiconductor (29.1): A semiconductor that con-ducts by means of free electrons.
pn-junction diode
pn-Junction diode (29.2): A semiconductor device having an n-side with a net positive charge, a p-side with a net negative charge, and a region around the junction without charge carriers.
p-type semiconductor
p-type semiconductor (29.1): A semiconductor that conducts by means of holes.
Transistor
transistor (29.2): A semiconductor device used in electronic circuits to amplify voltage changes.
Activity
activity (30.1): The number of decays per second, or decay rate, of a radioactive substance.
alpha decay
alpha decay (30.1): The radioactive decay process in which the nucleus of an atom emits an alpha particle.
Antiparticle
antiparticle (30.2): A particle of antimatter.
atomic mass unit
atomic mass unit (u) (30.1): Unit of mass equal to 1/12 the mass of the carbon-12 isotope.
atomic number
atomic number (z) (30.1): The number of protons in the nucleus of an atom.
beta decay
beta decay (30.1): The process of radioactive decay that occurs when a neutron is changed to a proton within the nucleus of an atom, and a beta particle and an antineutrino are emitted.
elementary particle
elementary particles (30.2): The three families of particles (quarks, leptons, and force carriers) that appear to make up all matter in the universe and through which matter interacts with other matter.
force carrier
force carriers (30.2): Elementary particles -photons, gluons, weak bosons, or yet-undetected gravitrons-that carry forces between matter.
gamma decay
gamma decay (30 1) The radioactive process of decay that takes place when the nucleus of an atom emits a gamma ray.
grand unification theory
grand unification theory (30.2): A theory in the process of development to unify strong force and electroweak force into one force.
half-life
half-life (30.1): The amount of time required for half the nuclei of a given quantity of a radioactive isotope to decay.
Lepton
leptons (30.2): Elementary particles like electrons or anti-neutrinos; leptons and quarks appear to compose all the matter in the universe.
mass number
mass number (A) (30.1): The sum of neutrons and protons in the nucleus of an atom.
neutrino
neutrino (30.2): A neutral, massless particle that carries momentum and energy and is emitted with the beta particle during beta decay.
nuclear reaction
nuclear reaction (30.1): Reaction in which the number of protons or neutrons in the nucleus of an atom changes.
nuclide
nuclide (30.1): The nucleus of an isotope.
pair production
pair production (30.2): The conversion of energy into matter-antimatter particle pairs.
positron
positron (30.2): An antielectron.
quark
quarks (30.2): Elementary particles that make up protons, mesons, and neutrons, and that together with leptons appear to make up all matter in the universe.
radioactive
radioactive (30.1) A material that undergoes radioactive decay and emits radiation.
strong nuclear force
strong nuclear force (30.1): Force that holds the protons and neutrons together in the nucleus of an atom.
transmute
transmuted (30.1): The change of an element into a different element by means of a change in nuclear charge.
weak nuclear force
weak nuclear force (30.2): A weak force acting in the nucleus apparent during radioactive decay.
binding energy
binding energy (31.1): The energy equivalent of the mass defect; it is converted to thermal energy in a fission reaction
breeder reactor
breeder reactor (31.2): A reactor that generates more fissionable fuel than it consumes.
chain reaction
chain reaction (31.2): Continual fission reactions that result from the release of neutrons from previous fission reactions.
control rod
control rod (31.2): A cadmium rod that is moved in and out of a pressurized water reactor to control the rate of chain reaction.
controlled fusion
controlled fusion (31.2): A type of fusion that could safely provide Earth with a nearly limitless energy source and no radioactive waste formation.
Enrichment
enrichment (31.2): The process that increases the number of fissionable nuclei.
fast neutron
fast neutron
fission
fission (31.2): Division of a nucleus into two or more fragments, resulting in a release of neutrons and energy.
Fusion
fusion (31.2): The process in which nuclei with small masses are combined to form a nucleus with a larger mass.
inertial confinement fusion
inertial confinement fission (31.2): A controlled fusion that uses deuterium, tritium, compression, and lasers.
mass defect
mass defect (31.1): The difference between the sum of the masses of individual nucleons and the actual mass.
Moderator
moderator (31.2): A material that causes fast neutrons to lose speed when the neutrons collide with it.
Nucleon
nucleon (31.1): Either a proton or a neutron.
slow neutron
slow neutron ( 31.2): A lower-energy neutron created when a fast neutron collides with a moderator
thermonuclear reaction
thermonuclear reaction (31.2): A nuclear fusion reaction.