2.7.B—Describe static friction between two surfaces

Describe static friction between two surfaces.

• Static friction may occur between the contacting surfaces of two objects that are not moving relative to each other.
• Static friction adopts the value and direction required to prevent an object from slipping or sliding on a surface. Relevant equation:
  • i. Slipping and sliding refer to situations in which two surfaces are moving relative to each other.
  • ii. There exists a maximum value for which static friction will prevent an object from slipping on a given surface. Derived equation: FFfs s ,, maxN µ=
• The coefficient of static friction is typically greater than the coefficient of kinetic friction for a given pair of surfaces.