L29 - Friction & Traction

• Friction is a force generated at the interface of 2 surfaces in contact when there is motion or a tendency for motion of 1 surface with respect to the other
• The magnitudes of maximum static friction & kinetic friction are determined by the coefficient of friction bw/ the 2 surfaces & by the normal reaction force pressing the 2 surfaces together

  • Once overcome friction force to start sliding, less force required to continue sliding
• The direction of friction force always opposes the direction of motion or motion tendency
• In sport sliding can be an advantage but the surface interaction may also play a significant risk for non-contact soft tissue injury