the tendency of an object to resist changes in its velocity
A force that opposes motion, resulting from the contact of two surfaces
Friction that opposes motion once the motion has already started.
Friction that opposes the initiation of motion
Newton's First Law
An object in motion (or at rest) will tend to stay in motion (or at rest) until it is acted upon by an outside force. Also known as Law of Inertia.
Newton's Second Law
When an object is acted on by one or more outside forces, the total force is equal to the mass of the object times the resulting acceleration. (total force = (mass) (acceleration)
Newton's Third Law
For every action, there is an equal and opposite reaction