Coefficient of Friction • Ratio of the frictional force and the normal force provides the coefficient of friction • μ=F_f/F_N Kinetic or Static Calculating the Force of Friction • The force of friction depends only upon the nature of the surface in contact (μ) and magnitude of the normal force FN • Combine with Newtons Second Las and FBDs to solve more involved problems 2007 Free Response Question 1