Mechanical Equilibrium: Forces and Resultants

This lecture covers the concept of mechanical equilibrium in structural mechanics, focusing on the isolation of systems, free-body diagrams, and the analysis of forces and moments in 2D and 3D. It explains the definition of forces, moments, and resultants, emphasizing the importance of system isolation and equilibrium conditions. The lecture also delves into the geometric and algebraic methods for calculating resultants and introduces the principles of moments and couples in 3D. Additionally, it discusses the concept of a couple as a pair of equal and opposite forces that produce independent moments. The presentation concludes with examples of applying equilibrium principles to analyze forces and moments in mechanical systems.