Contact Forces between Surfaces

Correctly analyze the forces generated by two surfaces in contact with each other.
- Determine the direction of the normal force exerted on an object when it is in contact with a surface.
- Recognize when friction forces are required, including which friction force (kinetic or static) is appropriate.
- Relate the magnitudes of the force of kinetic friction and the normal force.
- Recognize when the maximum force of static friction is required in a problem and how the maximum force of static friction is related to the normal.