7.13 The highly loaded cam, shown below, has a minimum radius of 10 [mm], is 20 [mm] wide and is subjected to a load of 4 [kN]. The cam rotates against a convex stationary follower that has a radius of 40 [mm]. The sliding speed at the point of contact is approximately 0.1 [m/s]. The cam is lubricated with oil that has a dynamic viscosity of no = 1.44 [Pas] at the operating temperature and a pressure-viscosity coefficient = 2.8108 [Pa]. The material of both cam and follower has a modulus of elasticity E = 2.0710 [Pa] and Poisson's ratio v = 0.3. Estimate the surface roughness of the cam and the follower necessary to prevent the occurrence of scuffing. (Ans. = 0.0768 [um]) R = 40 mm R = 10 mm +