If a body slides on a surface, it experiences friction F (a force against the direction of motion). Experiments show that |F| = |N| (Coulomb's

If a body slides on a surface, it experiences friction F (a force against the direction of motion). Experiments show that |F| = μ|N| (Coulomb's law of kinetic friction without lubrication), where N is the normal force (force that holds the two surfaces together; see Fig. 15) and the constant of proportionality μ is called the coefficient of kinetic friction. In Fig. 15 assume that the body weighs 45 nt (about 10 lb; see front cover for conversion). μ = 0.20 (corresponding to steel on steel), a = 30? the slide is 10 m long, the initial velocity is zero, and air resistance is negligible. Find the velocity of the body at the end of the slide.

-s(t)- Body (1)a A vt) N W Fig. 15. Problem 32