26.13. M http://www.ck12.org
26.13 M
machine
Any device that makes work easier by changing a force.
magnet
Object that attracts ferromagnetic materials such as iron.
magnetic domain
Area of a ferromagnetic material where the north and south poles of atoms are all lined up in the same
direction.
magnetic field
Area around a magnet where it exerts magnetic force.
magnetic force
Force of attraction or repulsion exerted by a magnet.
magnetic pole
North or south end of a magnet where the magnet exerts the most force.
magnetism
Ability of a material to respond to and exert magnetic force.
magnetosphere
Region surrounding Earth that is affected by Earth’s magnetic force; name for Earth’s magnetic field.
manipulated variable
Factor that is changed, or manipulated, by a researcher in a scientific experiment; also called independent
variable.
mass
Amount of matter in a substance or object.
mass number
Number of protons plus neutrons in an atom; about equal to the atom’s mass in atomic mass units (amu).
matter
Anything that has mass and volume.
mean
Average value of a set of measurements that is calculated by summing the individual measurements and then
dividing the total by the number of measurements.
mechanical advantage
Number of times a machine multiplies the input force; calculated as the output force divided by the input
force.
mechanical energy
Energy of an object that is moving or has the potential to move; calculated as the sum of an object’s kinetic
and potential energy.
mechanical wave
Disturbance in matter that transfers energy from one place to another.
melting
Process in which a solid changes to a liquid.
metal
Class of elements that are good conductors of electricity.
metallic bond
Force of attraction between a positive metal ion and valence electrons it shares with other ions of the metal.
metalloid
Class of elements that have some properties of metals and some properties of nonmetals.