Simple Twist: Moments of Inertia and Torsional Shear Stress

This lecture covers the concept of simple twist in torsion, focusing on the equilibrium equations, polar coordinates, and moments of inertia. It explains the calculation of second-order moments for various shapes and the translation effect of coordinate axes. The lecture also delves into the definition of the constant k in simple torsional shear stress and the stress state of circular torsion, emphasizing the pure shear stress. Additionally, it discusses circular and non-circular torsional strain, slip angles, and the angular strain in different section shapes. The instructor presents key results derived from elasticity theory, highlighting the importance of understanding moments of inertia and shear stress in torsion.