Newton's Second Law
Forces and Motion
When the resultant force is not zero
Physics Narrative for 11-14
Resultant forces change motion
- Most moving objects are acted upon by a
driving
force and retarding (often frictional) forces acting in the opposite direction to the motion. - When these forces add to zero (the resultant force is zero), the object maintains a constant speed.
- When the forces do not add to zero (there is a non-zero resultant force), the object will either speed up, slow down or change direction.