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Glossary
Glossary: Unit I Chapters 1–9 center of mass: the point at which all the mass of an object is considered to be Active Physics concentrated for calculations concerning motion of the object. acceleration: the change in velocity per unit time. centripetal acceleration: the inward radial v acceleration of an object moving at a a t constant speed in a circle. air resistance: a force by the air on a moving v2 a object; the force is dependent on the speed, R volume, and mass of the object as well as on centripetal force: a force directed towards the properties of the air, like density. the center that causes an object to follow a alternating current: an electric current that circular path. reverses in direction. mv2 F R amplitude: the maximum displacement of a closed system: a physical system on which particle as a wave passes; the height of a no outside influences act; closed so that wave crest; it is related to a wave’s energy. nothing gets in or out of the system and ampere: the SI unit for electric current; one nothing from outside can influence the ampere (1 A) is the flow of one coulomb of system’s observable behavior or properties. charge every second. concave lens: a lens that causes parallel light analog: a description of a continuously rays to diverge; a lens that is thicker at its variable signal or a circuit; an analog signal edges than in the center. can be represented as a series of waves. conduction: (of heat) the energy transfer angle of incidence: the angle a ray of light from one material or particle to another makes with the normal to the surface at the when the materials or particles are in direct point of incidence. contact. angle of reflection: the angle a reflected ray constructive interference: the result of makes with the normal to the surface at the superimposing different waves so that two point of reflection. or more waves overlap to produce a wave with a greater amplitude. antinode: a point on a standing wave where the displacement of the medium is at its convection: the heat transfer resulting from maximum. the movement of the heated substance, such as air or water currents. atom: the smallest particle of an element that has all the element’s properties; it converging lens: parallel beams of light consists of a nucleus surrounded by passing through the lens are brought to a real electrons. point or focus (convex lens) (if the outside index of refraction is less than that of the lens atomic mass unit: a standard unit of atomic material.); also called a convex lens. mass based on the mass of the carbon atom, which is assigned the value of 12. convex lens: a lens that causes parallel light rays to converge (if the outside index of baryon: a group of elementary particles that refraction is less than that of the lens are affected by the nuclear force; neutrons material); a lens that is thinner at its edges and protons belong to this group. than in the center.
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Glossary Unit 1 Chapters 1–9 Active Physics
coulomb: the SI unit for electric charge; one electrical resistance: opposition of a material coulomb (1 C) is equal to the charge of 6.25 to the flow of electrical charge through it: it x 1018 electrons. is measured in ohms (Ω); the ratio of the potential difference to the current. Coulomb’s Law: the relationship among V R electrical force, charges, and the distance I between the charges. electromagnet: a device that uses an electric q q 1 2 F k 2 current to produce a concentrated magnetic d field. crest: the highest point of displacement of a wave. electromagnetic waves: transverse waves that are composed of perpendicular electric and critical angle: the angle of incidence for magnetic fields that travel at 3 x 108 m/s in which a light ray passing from one medium a vacuum; examples of electromagnetic to another has an angle of refraction of 90º waves in increasing wavelength are gamma degrees. rays, x-rays, ultraviolet radiation, visible destructive interference: the result of light, infrared radiation, microwaves, and superimposing different waves so that two radio waves. or more waves overlap to produce a wave electron: a negatively charged particle with a with a decreased amplitude. charge of 1.6 x 10-19 coulombs and a mass -31 diffraction: the ability of a wave to spread of 9.1 x 10 kg. out as it emerges from an opening or moves entropy: a measure of the degree of disorder beyond an obstruction. in a system or a substance. digital: a description of data that is stored or focal length: the distance between the center transmitted as a sequence of discrete of a lens and either focal point. symbols; usually this means binary data (1s and 0s) represented using electronic or focus: the place at which light rays converge electromagnetic signals. or from which they appear to diverge after refraction or reflection; also called focal displacement: the difference in position point. between a final position and an initial position; it depends only on the endpoints, force: a push or a pull that is able to not on the path; displacement is a vector; it accelerate an object; force is measured in has magnitude and direction. newtons; force is a vector quantity. Doppler Effect: change in frequency of a frame of reference: a vantage point with wave of light or sound due to the motion of respect to which position and motion may the source or the receiver. be described. electric charge: a fundamental property of free fall: a fall under the influence of only matter; charge is either positive or negative. gravity. electric circuit: an electrical device that frequency: the number of waves produced provides a conductive path for electrical per unit time; the frequency is the reciprocal current to move continuously. of the amount of time it takes for a single wavelength to pass a point. electric current: the flow of electric charges v through a conductor; electric current is f measured in amperes. electric field: the region of electric influence defined as the force per unit charge.
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Glossary
friction: a force that acts to resist the relative joule: the SI unit for work and all other motion or attempted motion of objects that forms of energy; one joule (1J) of work is are in contact with each other. done when a force of one newton moves an object one meter in the direction of the galvanometer: an instrument used to detect, force. measure, and determine the direction of small electric currents. kinetic energy: the energy an object possesses because of its motion. gravitational potential energy: the energy a 1 body possesses as a result of its position in a KE mv2 2 gravitational field. lepton: a group of elementary particles that GPE mgh are not affected by the nuclear force; electrons belong to this group. gravity: the force of attraction between two light-year: the distance that light travels in bodies due to their masses. one year (9.46 x 1012 km). heat energy: a form of energy associated longitudinal pulse or wave: a pulse or wave in with the motion of atoms or molecules. which the motion of the medium is parallel Hooke’s Law: the distance of stretch or to the direction of the motion of the wave. compression of a spring is directly magnetic field: the region of magnetic proportional to the force applied to it. influence around a magnetic pole or a F k∆x moving charged particle. impulse: the product of force and the meson: a virtual particle that mediates the interval of time during which the force acts; strong, nuclear force of an atom; the impulse results in a change in momentum. protons and neutrons exchange mesons; the protons and protons exchange mesons; the impulse Ft ∆(mv) neutrons and neutrons exchange mesons. index of refraction: a property of a medium model: a representation of a process, system, that is related to the speed of light through or object. it; it is calculated by dividing the speed of light in vacuum by the speed of light in the momentum: the product of the mass and the medium. velocity of an object; momentum is a vector quantity. inertia: the natural tendency of an object to remain at rest or to remain moving with p = mv constant speed in a straight line. neutron: a subatomic particle that is part of inertial frame of reference: unaccelerated the structure of the atomic nucleus; a point of view in which Newton’s Laws hold neutron is electrically neutral. true. Newton’s Law of Gravitational Attraction: the inverse square relation: the relationship of a relationship among gravitational force, force to the inverse square of the distance masses, and the distance between the from the mass (for gravitational forces) or masses. the charge (for electrostatic forces). Gm m F 1 2 2 ionization energy: the energy required to free d an electron from an atom.
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Glossary Unit 1 Chapters 1–9 Active Physics
Newton’s Laws of Motion: open system: a physical system on which outside influences are able to act; open so Newton’s First Law of Motion: an object at that energy can be added and/or lost from rest stays at rest and an object in motion the system. stays in motion unless acted upon by an unbalanced, external force. parallax: the apparent difference of position of an object as seen from two different Newton’s Second Law of Motion: if a body is places, or points of view. acted upon by an external force, it will accelerate in the direction of the unbalanced period: the time required to complete one force with an acceleration proportional to cycle of a wave. the force and inversely proportional to the mass. periodic wave: a repetitive series of pulses; a wave train in which the particles of the F ma medium undergo periodic motion (after a set amount of time the medium returns to its Newton’s Third Law of Motion: forces come starting point and begins to repeat its in pairs; the force of object A on object B is motion). equal and opposite to the force of object B on object A. photoelectric effect: the emission of electrons from certain metals when light node: a point on a standing wave where the (electromagnetic radiation) of certain medium is motionless. frequencies shines on the metals. normal: at right angles or perpendicular to. photon: a particle of electromagnetic nuclear (strong) force: a strong force that radiation; a quantum of light energy. holds neutrons and protons together in the pitch: the quality of a sound dependent nucleus of an atom; the force operates only primarily on the frequency of the sound over very short distances. waves produced by its source nuclear fission: a nuclear reaction in which a polarized waves: disturbances where the massive, unstable nucleus splits into two or medium vibrates in only one plane. more smaller nuclei with a release of a large amount of energy. potential energy: energy that is dependent on the position of the object. nuclear fusion: a nuclear reaction in which nuclei combine to form more massive nuclei power: the time rate at which work is done with the release of a large amount of energy. and energy is transformed. W nucleon: the building block of the nucleus of P an atom; either a neutron or a proton. t probability: a measure of the likelihood of a nucleus: (of an atom): the positively charged given event occurring. dense center of an atom containing neutrons and protons. projectile: an object traveling through the air. ohm: the SI unit of electrical resistance; the symbol for ohm is Ω. proton: a subatomic particle that is part of the structure of the atomic nucleus; a proton Ohm’s Law: the relationship among is positively charged. resistance, voltage, and current. V I R
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Glossary
radiation: (heat transfer): electromagnetic kinetic energy of the molecules of a radiation strikes a material that can absorb material. it, causing the particles in the material to have more energy often resulting in a higher trajectory: the path followed by an object temperature. that is launched into the air. radioactive: a term applied to an atom that transverse pulse or wave: a pulse or wave in has an unstable nucleus and can which the motion of the medium is spontaneously emit a particle and become perpendicular to the motion of the wave. the nucleus of another atom. trough: the lowest point on a wave. ray: the path followed by a very thin beam vector: a quantity that has both magnitude of light. and direction. real image: an image that will project on a velocity: speed in a given direction; screen or on the film of a camera; the rays displacement divided by the time interval; of light actually pass through the image. velocity is a vector quantity, it has refraction: the change in direction (bending) magnitude and direction. of a light beam as it passes obliquely from virtual image: an image from which rays of one medium to a different one. reflected or refracted light appear to diverge, relativity: the study of the way in which as from an image seen in a plane mirror; no observations from moving frames of light comes directly from or passes through reference affect your perceptions of the the image. world. volt: the SI unit of electric potential; one volt scalar: a quantity that has magnitude, but (1 V) is equal to one joule per coulomb no direction. (J/C). Snell’s Law: describes the relationship wavelength: the distance between two between the index of refraction and the identical points in consecutive cycles of a ratio of the sine of the angle of incidence wave. and the sine of the angle of refraction. weight: the vertical, downward force exerted ∠ sin i on a mass as a result of gravity. n sin ∠ R solenoid: a coil of wire. Fg mg Special Theory of Relativity: the theory of work: the product of the displacement and space and time. the force in the direction of the displacement; work is a scalar quantity. specific heat: the amount of energy required to raise the temperature of 1 kg of a W = F d material by 1°C. E mc∆t speed: the change in distance per unit time; speed is a scalar, it has no direction. spring potential energy: the internal energy of a spring due to its compression or stretch. temperature: a measure of the average
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Glossary Unit 1I Chapters 10–12 Active Chemistry
Glossary: Unit II chemical formula: the combination of the Chapters 10–12 symbols of the elements in a definite Active Chemistry numerical proportion used to represent molecules, compounds, radicals, ions, etc. accuracy: how close the measured value is to chemical group: a family of elements in the the standard or accepted value of that periodic table that have similar electron measurement. configurations. acid: a substance that produces hydrogen chemical property: a characteristic that a ions in water, or is a proton donor. substance undergoes in a chemical reaction acid-base indicator: a dye that has a certain that produces new substance(s). color in an acid solution and a different chemical reaction: a process in which new color in a base solution. substance(s) are formed from starting alloy: a substance that has metal substance(s). characteristics and consists of two or more chemical test: a physical procedure or different elements. chemical reaction used to identify a anion: a negatively charged ion. substance. atom: the smallest representative part of an colligative property: a property such as element. freezing-point depression or boiling-point elevation whose physical value depends on atomic mass: atomic mass is determined by only the ratio of the particles of solute and the mass of the protons and neutrons of the solvent particles and not on their chemical atom. identities. atomic mass unit (amu): a unit of mass colloid: a mixture containing particles larger defined as one-twelfth of the mass of a than the solute but small enough to remain carbon-12 atom. suspended in the continuous phase of Avogadro’s number: the number of atoms another component. This is also called a contained in 12 grams of carbon-12. The colloidal dispersion. 23 number is 6.022 10 . combustion: the rapid reaction of a material base: a substance that releases hydroxide with oxygen accompanied by rapid ions (OH–) in water, or is a proton acceptor. evolution of flame and heat. binary compound: a compound formed from composite: a solid heterogeneous mixture of the combining of two different elements. two or more substances that make use of the bounce: the ability of an object to rebound properties of each component. to its original position when dropped from a compound: a material that consists of two or given height. more elements united together in definite catalyst: a substance that changes the speed proportion. of a chemical reaction without being concentration: a measure of the composition permanently changed itself. of a solution, often given in terms of moles cation: a positively charged ion. of solute per liter of solution. chemical change: a change that converts the conductivity: the property of transmitting chemical composition of a substance into heat and electricity. different substance(s) with different chemical covalent bond: a bond formed when two composition. atoms combine and share their paired electrons with each other.
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Glossary
decomposition: a chemical reaction in which flame test: an experimental technique or a single compound reacts to give two or process in identifying a metal from its more products. characteristic flame color. density: the mass per unit volume of a frequency: the number of waves per second material. or cycles per second or hertz (Hz). double-displacement reaction: a chemical fusion: nuclei of lighter atoms combining to reaction in which two ionic compounds form nuclei with greater mass and release of “exchange” cations to produce two new a large amount of energy. compounds. halogens: Group VIIA (17) on the periodic ductility: a property that describes how easy table consisting of fluorine, chlorine, it is to pull a substance into a new bromine, iodine, and astatine. permanent shape, such as, pulling into hydrocarbon: a molecular compound wires. containing only hydrogen and carbon. elasticity: the property of a material to resist inorganic compound: a compound not based deformation and return to its normal size or on molecular compounds of carbon. shape after a force has been applied to it. ion: an electrically charged atom or group of electrolysis: the conduction of electricity atoms that has acquired a net charge, either through a solution that contains ions or negative or positive. through a molten ionic compound that will induce chemical change. ionic bond: the attraction between oppositely charged ions. electromagnetic spectrum: the complete spectrum of electromagnetic radiation, such ionic compound: a compound consisting of as radio waves, microwaves, infrared, positive or negative ions. visible, ultraviolet, x-rays, and gamma rays. ionization energy: the energy required to remove an electron from a gaseous atom at electron: a negatively charged particle with a ground state. charge of 1.6 x 10-19 coulombs and a mass of 9.1 x 10-31 kg. isotope: atoms of the same element but different atomic masses due to different electron configuration: the distribution of number of neutrons. electrons in an atom’s energy levels. kinetic energy: a form of energy related to element: a substance in which all of the the motion of a particle atoms have the same atomic number. 1 2 emulsion: a colloid or colloidal dispersion of (KE 2 mv ). one liquid suspended in another. Law of Definite Proportions: the composition endothermic change or reaction: a change in of a pure substance is always the same or which energy in the form of heat is absorbed the elements of the compound always from the surrounding environment resulting combine in the same proportion by mass. in an increase in the internal energy of the system. luster: the reflection of light from the surface of a material described by its quality exothermic change or reaction: a change in and intensity. which energy in the form of heat is released from a system resulting in a decrease in the malleability: the property of a material to be internal energy of the system. able to be hammered into various shapes without breaking. fission: the process of breaking apart nuclei into smaller nuclei and with the release of a metal: classes of materials that exhibit the large amount of energy. properties of conductivity, malleability, reactivity, and ductility. Metal elements readily lose electrons to form positive ions.
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Glossary Unit 1I Chapters 10–12 Active Chemistry
mole: a collection of objects that contains pH: a quantity used to represent the acidity Avogadro’s number (6.022 1023). of a solution based on the concentration of molecular compound: two or more atoms hydrogen ions (pH log[H ]). bond together by sharing electrons (covalent phase change: the conversion of a substance bond). from one state to another state at a specific neutralization: the process of an acid and temperature and pressure. Example: solid to base reacting to form water and salt. liquid, liquid to gas, or solid to gas (sublimation). neutron: neutral subatomic particle with a mass of 1.675 10 24 g located in the physical change: a change that involves nuclei of the atom. changes in the state or form of a substance but does not cause any change in chemical noble gas: a family of elements (Group 18 or composition. VIIIA) of the periodic table. physical property: a property that can be nonmetal: elements that do not exhibit the measured without causing a change in the properties of conductivity, malleability, substance’s chemical composition. reactivity, and ductility. These elements tend to form negative ions. The oxides of the Planck’s constant: a proportionality constant elements are acidic. of the energy of a photon to its frequency, derived by Max Planck in 1900. His normal boiling point: the temperature at equation was: E hf and Planck’s constant which the vapor pressure of the pure liquid is (h) 6.626 10 34 J•s. equals 1 atm. polyatomic ion: an ion that consists of two normal freezing point: the characteristic or more atoms that are covalently bonded temperature, at 1 atm, at which a material and have either a positive or negative changes from a liquid state to its solid state. charge. normal melting point: the characteristic polymer: a substance that is a temperature, at 1 atm, at which a material macromolecule consisting of many similar changes from a solid state to its liquid state. small molecules (monomers) linked together nucleus: the very dense core of the atom that in long chains. contains the neutrons and protons. polymerization: a chemical reaction that orbit: the path of the electron in its motion converts small molecules (monomers) into around the nucleus of Bohr’s hydrogen large molecules (polymers). atom. potential energy: stored energy of the orbital: in the quantum mechanical model of material as a result of its position in an an atom, it is the region surrounding the electric, magnetic, or gravitational field. atomic nucleus in which the electron precipitate: an insoluble solid formed in a distribution is given by a wave function. liquid solution as a result of some chemical organic compound: a molecular compound reactions. of carbon. precision: the closeness of agreement of oxidation: the process of a substance losing several measurements of the same quantity. one or more electrons. product: the substance(s) produced in a oxidation number: a number assigned to an chemical reaction. element in a compound designating the proton: a positively charged subatomic number of electrons the element has lost, particle contained in the nucleus of an atom. gained, or shared in forming that The mass of a proton is 1.673 10 24g and compound. it has a charge of 1. period: a horizontal row of elements in the periodic table.
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Glossary
pure material: an element or compound that suspension: heterogeneous mixture that has a defined composition and properties. contains fine solid or liquid particles in a pure substance: a substance that contains fluid that will settle out spontaneously. By only one kind of particle. shaking the container they will again be dispersed throughout the fluid. radioactive: an atom that has an unstable nuclei and will emit alpha, positron, or beta synthesis reaction: a chemical reaction in particles in order to achieve more stable which two or more substances combine to nuclei. form a compound. reactants: the starting materials in a temperature: the measure of the average chemical reaction. kinetic energy of all the particles of the material. reactivity: a property that describes how readily a material will react with other texture: the characteristics of the surface of a materials. material, like how smooth, rough, or coarse it is. reduction: a process in which the substance under consideration gains electron(s). titration: an analytical procedure in which the concentration of an unknown solution is saturated solution: the maximum amount of added to a standard solution until a color solute that can be dissolved at a given change of some indicator indicates that temperature and pressure. equivalent quantities have reacted. single-displacement reaction: a reaction in Tyndall Effect: the scattering of a light beam which an element displaces or replaces as it passes through a colloid. another element in a compound. uniformity: the property of how consistent a solute: the substance that dissolves in a material is throughout. solvent to form a solution. valence electrons: the outermost electrons of solution: a homogeneous mixture of two or an atom. These electrons are used for more substances. chemical bonding of atoms. solvent: the substance in which a solute vaporization: the change of state from a dissolves to form a solution. liquid to a gas. strength: the property of how well a viscosity: a property related to the resistance material withstands the application of a of a fluid to flow. force. wavelength: the distance measured from sublimation: The change of state of a solid crest to crest of one complete wave or cycle. material to a gas without going through the liquid state. supersaturated solution: a solution containing more solute than a saturated solution and therefore not at equilibrium. This solution is not stable and cannot be maintained indefinitely. surface area: changing the nature of the reactants into smaller particles increases the surface exposed to react. Successful reaction depends on collision and increasing the area of the reactant increases the chance of a successful collision taking place. Lighting a log is more difficult than lighting wood shavings. The shavings have a greater surface area and speed up the reaction.
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