Lecture # 5 Friction and its types .pptx

Force of friction, coefgicie t of friction

1. Friction is defined as a force of resistance acting on a body which prevents or resists the slipping of a body relative to a second body. Experiments show that frictional forces act tangent (parallel) to the contacting surface in a direction opposing the relative motion or tendency for motion. Friction

2. Friction For each case we also have: Dry friction (Coulomb friction):  it occurs between the contacting surfaces of bodies in the absence of a lubricating fluid. Fluid friction:  it exists when the contacting surfaces are separated by a film of fluid (gas or liquid).