Nothing's linear in life and mechanics is no different. Every physical interaction we have with an object in this world results in a reaction and every such reaction has some degree of nonlinearity.
For instance, a simple leisure activity such as fishing has a fishing pole that acts in a nonlinear fashion.
Or a more serious note, studying stent deployment or concussions caused by head impact involves highly nonlinear systems.
What is the meaning of a nonlinear system and what makes a system nonlinear? This is the focus of the current lesson.
Here are the accompanying handout slides for this lesson.