Motion vocabulary.
friction
a force that opposes the motion of another object; making the object slow down and
eventually stop
position
a comparison of an object's location on a map to other things on the map
gravity
the force that pulls objects down towards Earth's surface
mass
the measure of the amount of matter in an object
matter
Anything that has mass and takes up space
acceleration/force relationship
the more force you apply, the greater the acceleration (change in speed or direction)