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Physical Science Vocabulary

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PHYSICAL SCIENCE VOCABULARY acceleration- The rate of change in atomic nucleus; has a charge of 2+, an velocity (a change in direction or a atomic mass of 4, and is the largest, change in speed). slowest, and least penetrating form of acid- A substance that produces radiation. hydrogen ions in solution; these amalgam- An alloy containing the solutions have a pH less than 7. element mercury; an example is dental alternating current (AC) - Electric fillings. current that reverses its direction in a ammeter- A galvanometer that regular pattern; the 60-Hz AC in our measures electrical current passing homes changes direction 120 times each through in amperes; connected in a second. series with the circuit. acid rain - Rain with a pH less than 5.6; amorphous- Something that has no produced by substances in the air specific shape; for example, a liquid or reacting with rainwater. gas. acoustics -The study of sound. ampere -The unit of measuring current, actinide- Any of the 14 radioactive the rate of flow of electrons in a circuit. elements having atomic numbers 90- amplification- The process of increasing 103; used in nuclear power generation the strength of an electric signal. and nuclear weapons. amplitude- In a wave, the distance from active solar heating - Collecting the the rest position of the medium to either sun's energy with solar panels, heating the crest or trough. water with that energy, and storing the amplitude modulated - (AM) waves - heated water to use the energy later. Radio waves whose amplitude is varied aerosol -A liquid sprayed from a with voice, music, video, or data for pressurized container; for example, a can transmission over long distances. of insect spray. angle of incidence - In waves, the angle air resistance - Frictional force air formed by the incident wave and the exerts on a moving object; acts opposite normal. in direction to the object's motion. angle of reflection - In waves, the angle alchemist -A medieval version of the formed by the reflected wave and the modern chemist; a practitioner who normal (perpendicular). blended primitive chemistry with magic, anhydrous- A chemical compound that seeking to turn ordinary metals into normally has water molecules attached gold. to its ions but from which water has been alcohol -Type of compound formed removed. when -OH groups replace one or more antacid -An "anti-acid," or a chemical hydrogen atoms in a hydrocarbon. that changes an acid substance to a allotropes -Different structural forms of neutral substance. the same element; for example, some antifreeze -A solute added to a solvent carbon molecules form soft graphite, to lower the temperature at which the whereas others form hard diamonds. solvent will freeze. alloy -A mixture consisting of a metal aqueous -Describes a solution made and one or more elements. with water. alpha particle - A particle of nuclear radiation emitted from a decaying PHYSICAL SCIENCE VOCABULARY Archimedes' principle - This Greek beta particle - A negatively charged mathematician stated that the buoyant electron or positively charged positron force on an object in a fluid is equal to emitted from a decaying atomic nucleus. the weight of the fluid displaced by the binary compound - A chemical object. compound composed of two elements; aromatic compounds - Chemical for example, sodium chloride. compounds that contain the benzene ring biogas Mixture of gases, mostly structure; most have distinctive odors. methane, produced when biomass is artificial satellite - Human-made device allowed to rot in the absence of air. that orbits Earth; used for biomass -Organic material from such communication, weather-monitoring, sources as wood, corn, and wastes from military, and scientific purposes. animals and crops. atomic number - The number of bionics The science of designing protons in an atom's nucleus. artificial replacements for parts of the average speed - A rate of motion human body that are not working determined by dividing the total distance properly. traveled by the total travel time. boiling point - The average atomic mass - The average temperature at which vapor mass of the mixture of an element's bubbles form in a liquid and isotopes. rise to the surface, balance -A device used in laboratories increasing evaporation. to measure mass; it works by balancing a Boyle's law - British mass to be determined with a standard scientist Robert Boyle mass that is known. stated that volume of a gas decreases balanced chemical equation - A when the pressure increases, provided chemical equation that has the same the temperature stays the same. number of atoms of each element on bubble chamber - Device filled with both sides of the equation. superheated liquid; used to detect and balanced forces - Forces that are equal monitor the path of charged nuclear in size and opposite in direction. particles, which leave a trail of bubbles bar graph - A type of graph used to as they pass though the chamber. show information collected buoyant force - Ability of a fluid to by counting; uses vertical or exert an upward force on an object horizontal bars of different immersed in the fluid. lengths to help people butane -A flammable gas; part of compare quantities. natural gas. base -A substance that byte -A basic unit of computer memory produces hydroxide ions (OH-) in the represents a character (number, solution; these solutions have a pH symbol, or alphabet letter); consists of 8 over 7. bits. Bernoulli's principle - The Swiss calorimeter- An instrument used to scientist Daniel Bernoulli stated that as measure changes in thermal energy. the velocity of a fluid increases, the carbohydrate An organic compound pressure exerted by the fluid decreases. having twice as many hydrogen atoms as oxygen atoms. PHYSICAL SCIENCE VOCABULARY carbon 14 dating - Age-determining which elements are in a compound and method for carbon-containing objects up their ratios. to 50,000 years old. chemical property - A characteristic of catalyst-A substance that speeds a a substance that indicates whether it can chemical reaction without itself being undergo a specific chemical change. permanently changed. chemical reaction - A change in which cathode ray tube (CRT) - Sealed glass one or more substances are converted to vacuum tube that uses electrons and different substances. fluorescent material to produce images chemical symbol - A shorthand way to on a screen. write the name of an element; for central processing unit - The main example: C for carbon, Ag for silver. circuit board inside a chemically stable - Describes an atom computer that performs the whose outer energy level is completely calculating and holds the filled with electrons. main memory. chemically unstable - Describes an centripetal acceleration - atom whose outer-most energy level is Acceleration toward the not filled with electrons so it seeks center of a circle by an object moving electrons from other atoms and thus along a circular path. forms compounds. centripetal force - The force that causes chloro Prefix that indicates presence of an object moving along a circular path to chlorine, as in tetrachloroethylene or move toward the center of the path. chlorofluorocarbon. ceramic A material made from dried CFC A group of compounds whose clay or claylike mixtures. decomposition releases chlorine atoms cermet A tough, heat-resistant material that destroy ozone molecules in the that has the properties of both a ceramic upper atmosphere. and an alloy; ceramic-metal. circuit A closed path through which chain reaction - A continuing series of electrons flow. fission reactions in which neutrons from circuit breaker - A device that protects fissioning nuclei cause other nuclei to an electrical circuit; if too much current split, releasing more neutrons, which flows, the device opens the circuit, split more nuclei, and so on. stopping the current. Charles's law - The volume of a gas cloud chamber - Device filled with increases when temperature increases, water- or ethanol-saturated air; used to provided the pressure stays the same. detect charged nuclear particles, which chemical bond - The force that holds leave a trail as they pass through. together the atoms in a compound; it coagulation Process that destroys occurs because atoms of most elements colloid structure; can be used to reduce a become more stable by losing, gaining, colloidal form of air pollution. and sharing electrons. coal A rock formed of ancient decayed chemical change - The plants; burned as a fossil fuel. change of substances to coefficient In a chemical equation, the different substances. number that represents the number of chemical formula - A units of each substance taking part in a precise statement that tells chemical reaction. PHYSICAL SCIENCE VOCABULARY coherent light - A beam of light in constant speed - Speed that does not which all the electromagnetic waves change. travel with the crests and troughs contraction Movement of molecules aligned; thus, the beam does not spread toward one another, so that they occupy out. a smaller space. colloid A heterogeneous mixture combustion Rapid burning. containing tiny particles that never settle composite A mixture of two materials, out; for example, milk and gelatin. one of which is embedded in the other. compression In compressional waves, compound Substance made of the the dense area of the wave. combined atoms of two or more compressional wave - A type of wave elements. where matter vibrates in the same compound machine - A combination of direction the wave travels. two or more simple machines. computer A device you can program to constant In an experiment, a factor that do calculations, make logical decisions, does not change. and manipulate data. control In an experiment, a standard for computer virus - Type of program comparison that is often needed to draw designed to infect a computer, erase a meaningful conclusion. data, scramble other programs, or fill up convection The transfer of energy by the so much memory that the system is bulk movement of matter in which harmed.
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