an object's change in positon relative to a reference point.
a group of objects that do not move relative to each other.
the change in postion of an object.
the distance traveled by an object divided by the time interval during which the motion occured.
a rate of motion determined by dividing the total distance traveled by the total travel time.
the speed of an object in a particular direction.
the sum of all the velocities of an object combined.
the rate at which velocity chanes over time; an object accelerates if its speed, direction, or both change.
decrease in velocity.
the acceleration directed toward the center of a circular path.
graph in which distance is measured against time.
A graph that can be used to plot the velocity of an object versus time and to determine the sign of an object's acceleration.
is a steady change in velocity.
the combination of all the forces acting on an object.
a single force whose external effects on a rigid body are the same as the effects of several actual forces acting on the body.
equal forces acting on one object in opposite directions.
two or more forces that are not equal and opposite of one another; can cause change in motion.
a force that opposes motion between two surfaces that are in contact.
the foce that resists the intention of sliding motion between two surfaces that are in contact and at rest.
the foce that opposes the movement of two surfaces that are in contact and are sliding over each other.
friction that occurs when one solid surface slides over another.
friction that occurs when an object rolls over a surface.
friction that occurs as an object moves through a fluid.
the science of shaping objects so they allow the easy flow of fluids around them to reduce drag.
substances that are applied to surfaces to reduce friction between them.
unwanted friction causing damage. ex: fire, carpet burn.
can be increased by making the surfaces that rub against each other rougher or by increasing the force pushing surfaces together. ex: scooping ice cream, movement.