Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
114 Cards in this Set
- Front
- Back
absorption spectrum |
A spectrum of dark lines across the pattern of spectral colours produced when light passes through a gas and the gas absorbs certain frequencies depending on the elements in the gas. |
|
ammeter |
"A device used to measure electric current |
|
amount of substance |
"SI quantity |
|
ampere |
"SI unit for electric current |
|
amplitude (xo) |
"The maximum displacement of a wave from its mean (or rest) position |
|
antinode |
A point of maximum amplitude along a stationary wave caused by constructive interference. |
|
area (A) |
"A physical quantity representing the size of part of a surface |
|
Celsius |
Measurment of Temperature |
|
charge |
see electric charge. |
|
coherence |
Two waves with a constant phase relationship. |
|
components |
"Parts of electric circuits |
|
conductor |
A material with a high number density of conduction electrons and therefore a low resistance. |
|
conservation of charge |
Physical law stating charge is conserved in all interactions; it cannot be created nor destroyed. |
|
conservation of energy |
"Physical law stating energy cannot be created or destroyed |
|
conventional current |
A model used to describe the movement of charge in a circuit. Conventional current travels from + to –. |
|
coulomb |
"Unit of electric charge (C) |
|
current |
see electric current. |
|
de Broglie equation |
"An equation expressing the wavelength of a particle as a ratio of Planck’s constant and the particle’s momentum |
|
degree Celsius |
"Unit for temperature |
|
diffraction |
When a wave spreads out after passing around an obstacle or through a gap. |
|
distance (d) |
"How far one position is from another |
|
drift velocity |
The average velocity of an electron as it travels through a wire due to a p.d. |
|
dynamo |
A device that converts kinetic energy into electrical energy. |
|
efficiency |
The ratio of useful output energy to total input energy. |
|
elastic limit |
The point at which elastic deformation becomes plastic deformation. |
|
electric charge (Q or q) |
"Physical property |
|
electric current (I) |
"A flow of charge. An SI quantity |
|
electrolyte |
A fluid that contains ions that are free to move and hence conduct electricity. |
|
electromagnetic wave |
A self-propagating transverse wave that does not require a medium to travel through. |
|
"electromotive force |
e.m.f. " |
|
electron |
Negatively charged sub-atomic particle. Conduction electrons travel around circuits creating an electric current. |
|
electron diffraction |
"The process of diffracting an electron through a gap (usually between atoms in a crystal structure |
|
electron flow |
"The movement of electrons (usually around a circuit) |
|
electronvolt |
One electronvolt is the energy change of an electron when it moves through a potential difference of one volt. Its value is 1.60 × 10–19 J. |
|
emission spectrum |
"A pattern of colours of light |
|
energy (E) |
"The ability to do work |
|
energy levels |
One of the specific energies an electron can have when in an atom. |
|
equilibrium |
When there is zero resultant force and zero torque acting on an object. |
|
force (F) |
"A push or a pull on an object |
|
frequency (f) |
"The number of oscillations per unit time |
|
fundamental frequency |
The lowest frequency in a harmonic series where a stationary wave forms. |
|
fuse |
"An electrical component designed to heat up and then melt if too much current passes through it. |
|
gamma rays |
A form of electromagnetic wave with wavelengths between 10–16 m and 10–9 m. Used in cancer treatment. |
|
gradient of a graph |
The change in y-axis over the change in the x-axis (rise over step). |
|
gravitational potential energy |
The energy stored in an object by virtue of the object being in a gravitational field. |
|
harmonics |
Whole-number multiples of the fundamental frequency of a stationary wave. |
|
infrared |
A form of electromagnetic wave with wavelengths between 7.4 ´ 10–7 and 10–3 m. Used in remote controls. |
|
insulator |
A material with a small number density of conduction electrons and therefore a very high resistance. |
|
intensity |
"The energy incident per square metre of a surface per second |
|
interference |
The addition of two or more waves (superposition) that results in a new wave pattern. |
|
internal resistance (r) |
"The resistance of a battery or cell |
|
I–V characteristic |
A graph to show how the electric current through a component varies with the potential difference across it. |
|
joule |
"Unit of energy (J) |
|
kelvin |
"SI unit of temperature (K) |
|
kilowatt |
"Unit of power (kW) |
|
kilowatt-hour |
"Unit of energy (kWh) |
|
kinetic energy |
"The work an object can do by virtue of its speed |
|
Kirchhoff’s first law |
The sum of the currents entering any junction is always equal to the sum of the currents leaving the junction (a form of conservation of charge). |
|
Kirchhoff’s second law |
The sum of the e.m.f.s is equal to the sum of the p.d.s in a closed loop (a form of conservation of energy). |
|
"light dependent resistor |
LDR " |
|
"light emitting diode |
LED " |
|
line spectrum |
A spectrum produced by a material that contains only certain frequencies due to electron transitions between energy levels. |
|
longitudinal wave |
"A wave where the oscillations are parallel to the direction of wave propagation |
|
Malus’ law |
A physical law describing the change in intensity of a transverse wave passing through a Polaroid analyser. |
|
mass (m) |
"SI quantity |
|
microwaves |
A form of electromagnetic wave with wavelengths between 10–4 and 10–1 m. Used in mobile phones. |
|
monochromatic light |
Light waves with a single frequency (or wavelength). |
|
node |
A point that always has zero amplitude along a stationary wave caused by destructive interference. |
|
ohm |
"Unit of resistance (?) |
|
Ohm’s law |
"The electric current through a conductor is proportional to the potential difference across it |
|
parallel circuit |
A type of circuit where the components are connected in two or more branches and therefore provide more than one path for the electric current. |
|
perpendicular |
At right angles (90° or p/2 rad) to. |
|
period (T) |
"The time taken for one complete pattern of oscillation |
|
phase difference (f) |
"The difference by which one wave leads or lags behind another. For example |
|
photocell |
A component that reduces its resistance when light shines on it due to photoelectric emission of electrons. |
|
photoelectric effect |
The emission of electrons from the surface of material when electromagnetic radiation is incident on the surface. |
|
photon |
"A quantum of light |
|
Planck constant (h) |
Constant used in quantum physics; 6.63 × 10–34 J s. |
|
plane polarised wave |
A transverse wave oscillating in only one plane. |
|
polarisation |
"The process of turning an unpolarised wave into a plane polarised wave (for example |
|
"potential difference |
p.d. " |
|
potential divider |
A type of circuit containing two components designed to divide up the p.d. in proportion to the resistances of the components. |
|
power (P) |
"The rate of doing work |
|
progressive wave |
A wave that travels from one place to another. |
|
quantum |
A discrete quantity of energy proportional in magnitude to the frequency of the radiation it represents |
|
radian (rad) |
"Unit of angle or phase difference |
|
radio waves |
A form of electromagnetic wave with wavelengths between 10–1 and 104 m. Used in telecommunications. |
|
reflection |
"When waves rebound from a barrier |
|
refraction |
When waves change direction when they travel from one medium to another due to a difference in the wave speed in each medium. |
|
resistance (R) |
"A property of a component that regulates the electric current through it. Measured in ohms (?) |
|
resistivity (r) |
The ratio of the product of resistance and cross-sectional area of a component and its length (best defined by using the equation r = RA/l). |
|
semiconductor |
A material with a lower number density of conduction electrons than a conductor and therefore a higher resistance. |
|
series circuit |
A type of circuit where the components are connected end to end and therefore provide only one path for the electric current. |
|
spectral line |
A line relating to a specific frequency either missing from an absorption spectrum or present in an emission spectrum. |
|
spectrum |
"A collection of waves with a range of frequencies |
|
standing wave |
An alternative name for a stationary wave. |
|
stationary wave |
A wave formed by the interference of two waves travelling in opposite directions. |
|
superposition |
The principle that states that when two or more waves of the same type exist at the same place the resultant wave will be found by adding the displacements of each individual wave. |
|
temperature (T or K) |
"SI quantity |
|
thermistor |
A component that changes its resistance depending on its temperature. An NTC thermistor’s resistance reduces as the temperature increases. |
|
time interval (t) |
"SI quantity |
|
transverse wave |
"A wave where the oscillations are perpendicular to the direction of wave propagation |
|
ultraviolet |
A form of electromagnetic wave with wavelengths between 10–9 and 3.7 × 10–7 m. Causes sun tanning. |
|
volt |
"Unit of potential difference and e.m.f (V) |
|
voltmeter |
Device used to measure the p.d. across a component. It is connected in parallel across a component. |
|
watt |
"Unit of power (W) |
|
wave |
A series of vibrations that transfer energy from one place to another. |
|
wavelength (l) |
"The smallest distance between one point on a wave and the identical point on the next wave (e.g. the distance from one peak to the next peak) |
|
wave–particle duality |
The theory that states all objects can exhibit both wave and particle properties. |
|
work (W) |
"The product of force and the distance moved in the direction of the force |
|
work function energy (?) |
"The minimum energy required to release an electron from a material |
|
X-rays |
A form of electromagnetic wave with wavelengths between 10–12 and 10–7 m. Used in X-ray photography. |
|
Young’s double slit |
An experiment to demonstrate the wave nature of light via superposition and interference. |
|
Young modulus (Y) |
"The ratio of tensile stress to tensile strain |