Shear and Moment Diagrams for Internal Forces - Intro to Structural Analysis

This video presents the theory and purpose of shear and moment (i.e., internal force) diagrams.

The internal forces represent the stresses in the beam caused by beam bending or by axial forces. These internal forces may be calculated by hand using equilibrium. However, it is more common to draw the shear and moment diagrams that represent these internal forces along the entire length of the structure.

Both the derivative and integral (area) forms for the internal force equations are given. Then the diagrams are created for an example determinate beam.