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the rate at which velocity changes, an object accelerates if its speed changes, if its direction changes, or if both change


the maximum distance a wave vibrates from its rest position

Chemical change

a change that occurs when one or more substances are changed into entirely new substances with different properties

Chemical energy

the energy of a compound that changes as its atoms are rearranged to form a new compound; chemical energy is a form of potential energy

Chemical property

a property of matter that describes a substance based on its ability to change into a new substance with different properties

Chemical reaction

the process by which one or more substances undergo change to produce one or more different substances


a pure substance composed of two or more elements that are chemically combined


the transfer of thermal energy from one substance to another through direct contact; conduction can also occur within a substance


a transfer of thermal energy by the movement of liquid or gas


the amount of matter in a given space, mass per unit volume

Electric circuit

a complete, closed path through which electric charges flow


energy made available by the flow of electric charge through a conductor


a pure substance that cannot be separated or broken down into simpler substances by physical or chemical means


the ability to do work


become larger in size or volume or quantity


a push or a pull; all forces have both size and direction


the number of waves produced in a given amount of time


a force that opposes motion between 2 surfaces that are touching


energy due to an objects position above the Earth's surface


a force of attraction between objects that is due to their masses


the transfer of energy between objects that are at different temperatures


the tendency of all objects to resist any change in motion

Kinetic energy

the energy of motion; depends on speed and mass


a type of energy that travels as an electromagnetic wave

Longitudinal wave

a wave in which the particles of the medium vibrate back and forth along the path that the wave travels


having the properties of a magnet

Magnetic field

the region around a magnet in which magnetic forces can act


the ability of a substance to be pounded into thin sheets


the amount of matter something is made of

Mass number

the sum of the protons and the neutrons in an atom

Mechanical energy

the total energy of motion and position of an object


a combination of 2 of more substances that are not chemically combined


a neutral group of atoms held together by covalent bonds


a property of a moving object that depends on the objects mass and velocity


an objects change in position over time when compared with a reference point

Neutral atom

has no overall charge because there are equal numbers of protons and electrons

Newton's 1st Law

objects at rest tend to stay at rest, objects in motion tend to stay in motion

Newton's 2nd Law

the acceleration of an object depends on the mass of the object and the amount of force applied

Newton's 3rd Law

For every action there is an equal and opposite reaction

Noble gases

the unreactive elements in group 18 of the periodic table; their atoms have 8 valence electrons except Helium


elements that are dull and are poor conductors of thermal energy and electric current

Nuclear energy

the form of energy associated with changes in the nucleus of an atom

pH scale

a measurement scale of hydronium ion concentration in a solution pH 7 neutral, less than 7 acidic, more than 7 basic

Physical change

a change that affects one or more physical properties of a substance; many physical changes are easy to undo

Physical property

a property of matter that can be observed or measured without changing the identity of the matter


how high or low a sound is perceived to be

Potential energy

the energy of position or shape


the transfer of energy through matter or space as electromagnetic waves, such as visible light and infrared waves


the starting materials in a chemical reaction


ready susceptibility to chemical change

Series circuit

a circuit in which all parts are connected in a single loop

Solar energy

energy from the sun


the ability to dissolve in another substance


longitudinal waves created by vibrations


the rate at which an object moves


a measure of how hot or cold something is

Transverse wave

a wave in which the particles of the waves medium vibrate perpendicular to the direction the wave is traveling


the speed of an object in a particular direction


the complete back-and-forth motion of an object


the distance between one point on a wave and the corresponding point on an adjacent wave in a series of waves


a measure of the gravitational force exerted on an object, usually by the Earth


the action that results when a force causes an object to move in the direction of the force

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