Friction Models: Dry and Viscous

This lecture covers the models for dry friction, including static and kinetic coefficients, as well as approximate values for different surfaces. It also explains the concept of viscous friction, where the frictional force is proportional to velocity. The lecture further discusses the Hooke's law for spring force and provides guidance on problem-solving strategies in mechanics. Through examples, it illustrates the application of forces in ballistic motion without friction, emphasizing the representation of forces and the equations of motion. The integration of these equations leads to the trajectory of the projectile, highlighting the importance of choosing appropriate coordinate systems.