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Vocabulary
Vocab Ch. 1-10 * Vocab Ch. 11-20 * Vocab Ch. 21-31
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elastic collision
elastic collision (11.2): A collision in which the kinetic energy remains unchanged.
elastic potential energy
elastic potential energy (11.1): The potential energy stored in an object that is released as kinetic energy when the object undergoes a change in form or shape.
gravitational potential energy
gravitational potential energy (11.1): The stored energy in a system resulting from gravitational interaction between masses.
inelastic collision
inelastic collision (11.2): A collision in which the kinetic energy decreases.
law of conservation of energy
law of conservation of energy (11.2): The energy in a closed, isolated system is constant.
mechanical energy
mechanical energy (11.2): The sum of kinetic energy and gravitational potential energy in a given system.
reference level
reference level (11.1): An arbitrary position selected to solve a problem.
absolute zero
absolute zero (12.1): The temperature at which no further
thermal energy can be removed from an object; usually shown as -273°C.
boiling point
boiling point (12.2): The specific temperature at which added thermal energy causes a substance to change from a liquid to a gaseous state.
Calorimeter
calorimeter (12.1): A device that provides a closed, isolated system with which to measure changes in the thermal energy of a substance.
Conduction
conduction (12.1): The process that transfers kinetic energy when particles collide.
Convection
convection (12.1): The transfer of heat by means of motion in a fluid.
Entropy
entropy (12.2): A measure of the disorder of a system.
first law of thermodynamics
first law of thermodynamics (12.2): The total increase in the thermal energy of a system is the sum of the heat added to it and the work done on it.
Heat
heat (12.1): The energy transferred between two objects because of a difference in temperature.
heat engine
heat engine (12.2): A device that converts thermal energy to mechanical energy.
heat of fusion
heat of fusion (12.2): The amount of energy required to melt one kilogram of a substance.
heat of vaporization
heat of vaporization (12.2): The amount of thermal energy required to vaporize one kilogram of a liquid.
Kelvin
kelvin (12.1): An interval on the Kelvin scale, equal to the size of one Celsius degree.
kinetic-molecular theory
kinetic-molecular theory (12.1): Description of matter as being made up of tiny particles in random, constant motion.
melting point
melting point (12.2): The temperature at which added thermal energy overcomes the forces holding the particles of a substance together, causing the substance to change from a solid to a liquid state.
Radiation
radiation (121) The transfer of energy by electromagnetic waves.
second law of thermodynamics
second law of thermodynamics (12.2): States that the entropy of the universe is always maintained or increased.
specific heat
specific heat (12.1): The amount of energy that must be added to a material to raise the temperature of a unit mass one temperature unit.
Temperature
temperature (12 1) The 'hotness" of an object as measured using a specific scale.
thermal energy
thermal energy (12.1): The overall energy of motion of the particles of an object.
thermal equilibrium
thermal equilibrium (12.1): The state where the rate of energy transfer between bodies becomes equal and the bodies will be at the same temperature.
Thermodynamics
thermodynamics (12.1): The study of heat.
Thermometer
thermometer (12.1): A device that measures temperature.
Adhesion
adhesion (13.1): The electromagnetic force of attraction that acts between particles of different substances.
amorphous solid
amorphous solids (13.2): Solids with definite volume and shape but no regular crystal structure.
Archimedes’ principle
Archimedes' principle (13.1): The buoyant force on an object immersed in a fluid is equal to the weight of the fluid displaced by the object.
Bernoulli’s principle
Bernoulli's principle (13.1): The pressure exerted by a fluid decreases as its velocity increases.
buoyant force
buoyant force (13.1): The upward force exerted on an object immersed in fluid.
capillary action
capillary action (13.1): The rise of liquid in a narrow tube that occurs because the adhesive forces between glass and liquid molecules are stronger than the cohesive forces between liquid molecules.
coefficient of linear expansion
coefficient of linear expansion (13.2): The length change divided by the original length and by temperature change.
coefficient of volume expansion
coefficient of volume expansion (13.2): The volume change divided by original volume and by temperature change.
cohesive force
cohesive forces (13.1): The electromagnetic forces of attraction that like particles exert on one another.
Condensation
condensation (13.1): The process where particles of liquid that have evaporated into the air return to the liquid phase due to a decrease in kinetic energy or temperature.
crystal lattice
crystal lattice (13.2): A fixed, regular arrangement of atoms.
Evaporation
evaporation (13.1): The change from liquid to vapor state.
Fluid
fluid (13.1): A material that flows and has no definite shape.
Pascal
pascal (Pa) (13.1): The SI unit of pressure; one newton per square meter.
Pascal’s principle
Pascal's principle (13.1): Any change in applied pressure on a confined fluid is transmitted undiminished through the fluid.
Plasma
plasma (13.2): The gaslike state of matter made up of positively charged ions or negatively charged electrons or a mixture of them.
Pressure
pressure (13.1): The force applied to a surface.
surface tension
surface tension (13.1): The tendency of the surface of a liquid to contract to the smallest area possible.
thermal expansion
thermal expansion (13.2): The increase in length or volume of a material when heated.
Volatile
volatile (13.1): Describes a liquid that evaporates quickly at a relatively low temperature.
Antinode
antinode (14.2): The point of largest amplitude when two wave pulses meet of two superimposed waves.
constructive interference
constructive interference (14.2): Superposition of waves resulting in increased wave displacement.
continuous wave
continuous wave (14.1): A regularly repeating sequence of wave pulses.
Crest
crest (14.1): The high point of a wave
destructive interference
destructive interference (14.2): Superposition of waves with opposite but equal amplitudes.
Diffraction
diffraction (14.2): The bending of waves around a barrier.
Frequency
frequency (f) (14.1): In any periodic motion, the number of complete oscillations measured in hertz.
incident wave
incident wave (14.2): A wave that strikes the boundary between two media.
Interference
interference (14.2): The interaction of two or more waves.
law of reflection
law of reflection (14.2): The angle of incidence is equal to the angle of reflection.
longitudinal wave
longitudinal wave (14.1): A wave that displaces matter parallel to the direction of wave motion.
Node
node (14.2): The stationary point where two equal wave pulses meet and displacement is zero.
principle of superposition
principle of superposition (14.2): The displacement of a medium caused by two or more waves is the algebraic sum of the displacements of the individual waves.
reflected wave
reflected wave (14.2): A returning wave that is either inverted or displaced in the same direction as the incident wave.
Refraction
refraction (14.2): A change in the direction of waves crossing a boundary between two different media.
standing wave
standing wave (14.2): A wave with stationary nodes and antinodes.
surface wave
surface wave (14.1): A wave that displaces matter both parallel and perpendicular to the direction of wave motion.
transverse wave
transverse wave (14.1): A wave that displaces matter perpendicular to the direction of wave motion.
trough
trough (14.1): The low point of a wave.
Wave
wave (14.1): A rhythmic disturbance that carries energy through matter or space.
Wavelength
wavelength (l) (14.1): The shortest distance between points where the wave pattern repeats itself.
wave pulse
wave pulse (14.1): A single disturbance traveling through a medium.
Beat
beat (15.2): Oscillation of wave amplitude that occurs as a result of the superposition of two sound waves having nearly identical frequencies.
closed-pipe resonator
closed-pipe resonator (15.2): A hollow tube with one closed end and a sound source at the other end.
Consonance
consonance (15.2): A pleasant set of pitches.
Decibel
decibel (dB) (15.1): Unit of sound level.
Dissonance
dissonance (15.2): An unpleasant set of pitches.
Doppler shift
Doppler shift (15.1): A change in sound frequency due to the relative motion of either the source or the detector.
fundamental
fundamental (15.2): The lowest frequency of sound produced by a musical instrument.
harmonic
harmonics (15.2): Higher frequencies of sound that are multiples of the fundamental frequency produced by a musical instrument
octave
octave (15.2): Two musical notes with frequencies related by a 1:2 ratio.
open-pipe resonator
open-pipe resonator (15.2): A hollow tube, with both ends open, that resonates with a sound source.
Pitch
pitch (15.1): The frequency of a sound wave.
sound level
sound level (15.1): A logarithmic scale that measures amplitude in decibels.
Timbre
timbre (15.2): Tone color, or sound quality determined by the frequencies and intensities of complex waves.
Candela
candela (cd) (16.1): The SI base unit of luminous intensity; candle power.
complementary color
complementary color (16.2): Two colors of light that when added together produce white light.
dye
dye (16.2): A molecule that absorbs some light wavelengths and reflects or transmits others.
illuminance
illuminance (16.1): The rate at which light falls on a surface; measured in lux.
illuminated
illuminated (16.1): A body that reflects light waves produced by an outside source.
light
light (16.1): Electromagnetic radiation with wavelengths from 400 to 700 nm.
lumen
lumen (16.1): Unit of luminous flux.
luminous
luminous (16.1): A body that emits light waves.
luminous flux
luminous flux (16.1): The rate at which light is emitted from a light source; measured in lumens.
lux
lux (16.1): Unit of illuminance; lumens per square meter.
Opaque
opaque (16.2): A material that absorbs or reflects light, not allowing objects to be seen through it.
Pigment
pigment (16.2): A colored material that absorbs certain colors and reflects or transmits other colors.
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.
primary color
primary color (16.2): Color from which other colors can be derived.
primary pigment
primary pigment (16.2): A pigment that absorbs only one color from white light.
ray model
ray model (16.1): Light moves in a straight-line path through a medium.
ray optics
ray optics (16.1) The use of ray diagrams to study the travel of light, also called geometric optics.
secondary color
secondary color (16.2): Color formed by a pair of primary colors.
secondary pigment
secondary pigment (16.2): A pigment that absorbs two primary colors from white light and reflects one.
spectrum
spectrum (16.2): The ordered arrangement of wavelengths.
thin-film interference
thin-film interference (16.2): Light interference caused by reflection from the front and back surface of a thin layer of liquid or solid.
translucent
translucent (16.2): A material that transmits light but distorts its path.
transparent
transparent (16.2): A material that transmits light without distorting images.
angle of refraction
angle of refraction (17.1): The angle the refracted ray makes with the normal to the surface.
critical angle
critical angle (17.2): The incident angle unique to a substance that causes the refracted ray to lie along the boundary of the substance.
diffuse reflection
diffuse reflection (17.1): The scattered, fuzzy reflection from a rough surface where light is randomly reflected.
Dispersion
dispersion (17.2): Variation of the speed of light through matter resulting in separation of light into a spectrum.
index of refraction
index of refraction (17.1): The ratio of the speed of light in a vacuum to its speed in a material
optically dense
optically dense (17.1): Materials with larger indices of refraction with respect to other materials.
regular reflection
regular reflection (17.1): Reflection off a smooth surface, such as a mirror, where light is reflected back to the observer in parallel beams, producing a clear image.
Snell’s law
Snell's law (17.1): The ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant.
total internal reflection
total internal reflection (17.2): Occurs when light is incident on the boundary to a less optically dense medium at an angle so large there is no refracted ray.
achromatic lens
achromatic lens (18.2): A lens for which all light colors have the same focal length.
chromatic aberration
chromatic aberration (18.2): Variation in focal length of a lens with the wavelength of light.
concave lens
concave lens (18.2): A diverging lens, thicker at its outer edge than at its center.
concave mirror
concave mirror (18.1): A mirror that reflects light from its inwardly curved surface and produces either inverted, real images or upright, virtual images.
convex lens
convex lens (18.2): A converging lens, thinner at its outer edge than at its center.
convex mirror
convex mirror (18.1): A spherical mirror that reflects light from its outer surface and produces virtual, reduced, upright images.
erect image
erect image (18.1): A mirror image that points in the same direction as the reflected object.
focal length
focal length (18.1): The distance from the focal point to the mirror along the principal axis.
focal point
focal point (18.1): The point where parallel light rays converge or appear to diverge after reflecting from a mirror or refracting from a lens.
Image
image (18.1): Reproduction of object formed with mirrors or lenses.
Lens
lens (18.2): A transparent optical device, with a larger refractive index than air, used to converge or diverge light.
lens/mirror equation
lens/mirror equation (18.1): 1/f= 1/d1+ 1/d0, where f is the focal length, d1 is the image distance, and d0 is the object distance.
Magnification
magnification (18.1): The optical enlargement of an object; the ratio of the size of the image to the size of the object.
Object
object (optics) (18.1): A source of diverging light rays; may be luminous or illuminated.
plane mirror
plane mirror (18.1): A flat, smooth surface that reflects light rays by regular reflection, not by diffuse reflection. Forms a virtual, erect image the same size as the object and the same distance behind the mirror as the object is in front.
principal axis
principal axis (18.1): A straight line perpendicular to the surface of a spherical mirror at its center. (18.2) Line perpendicular to the plane of a lens passing through its center.
real image
real image (18.1): An optical image formed when light rays converge and pass through the image, producing an image that can be viewed on paper or projected onto a screen.
spherical aberration
spherical aberration (18.1): The image defect of a spherical mirror that does not allow parallel light rays far from the principal axis to converge at the focal point.
virtual image
virtual image (18.1): The point from which light rays appear to diverge without actually doing so.
coherent wave
coherent waves (19.1): Waves that are in phase-the wave crests and troughs reach the same point at the same time.
diffraction grating
diffraction grating (19.2): A device with parallel ridges that reflects light and forms an interference pattern.
interference fringes
interference fringes (19.1): The pattern of dark and light bands on a screen due to constructive and destructive interference of light waves passing through two narrow, closely spaced slits.
monochromatic light
monochromatic light (19.1): Light of only one wavelength.
Rayleigh criterion
Rayleigh criterion (19.2): When the central bright band of one star falls on the first dark band of the second, the two stars will be just resolved.
charging by conduction
charging by conduction (20.2): Charging a neutral object by touching it with a charged object.
charging by induction
charging by induction (20.2): Charging a neutral object by bringing it close to a charged object, causing a separation of charges, then removing the object to be charged, trapping opposite but equal charges.
Conduction
Conduction (20.2) Movement of charges. Materials known as conductors, such as metals, allow charges to move about easily.
Coulomb
coulomb (C) (20.2): The SI unit of electrical charge.
Coulomb’s law
Coulomb's law (20.2): The magnitude of a force between two charges varies directly with the magnitude of the charges and inversely with the square of the distance between them.
Electroscope
electroscope (20.2): A device used to determine electrical force.
Electrostatics
electrostatics (20.1): The study of electrical charges at rest.
elementary charge
elementary charge (20.2): The magnitude of the charge of an electron or proton, 1.60 x 10-19 C.