At the end of this section you should be able to:

1. Create FBD for internally-cut systems in 2D and 3D

   • Use standard convention for directions of forces in beams

2. Use FBD to create equations to solve for internal loads

Strength Introduction connects equilibrium to strength of materials by showing how to find the internal loads that drive stress and deformation. You will use the cut section method to create free body diagrams of internally cut members in 2D and 3D, apply the standard beam sign convention for internal forces and moments, and write equilibrium equations to solve for internal resultants such as axial force, shear force, torsion, and bending moment at a specified point or at a specified cut angle.