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Abstract In this work, we developed a laboratory guide that can be applied in both basic and advanced courses of classical mechanics. It consists of an experimental study of the normal force acting on a small metallic sphere as it rolls along certain curvilinear profiles. Specifically, we considered circular and elliptic profiles, fabricated with a 3D printer. In the method, the sphere’s motion is filmed using a smartphone camera. We also model the system using Newton’s second law, which governs its dynamics. Then, using video analysis, we estimate the magnitude of the normal force along the sphere’s trajectory. These results were used to estimate the height at which the sphere loses contact with the profile’s surfaces, at the point where the normal force is zero. We demonstrate the importance of possible dissipative effects and of the rotational motion, showing how the theoretical aspects addressed during the classes are related with practical and real aspects of the experiment, evidencing their influences on the position where the sphere loses contact with the surface by means of a direct comparison between experimental and theoretical results. The theoretical results describe a sphere that only slides without friction, for which the mechanical energy associated with the translational motion is conserved.