## Topics

- Stress
- Strain
- Principal Stresses & Strains
- Hooke's Law

## Summary

This chapter on introductory mechanics will review the basics of small strain linear
elastic mechanics. All the complexities of finite deformations and rotations will be
postponed until later. Nevertheless, this chapter is still relevant to
structural analyses of aircraft, buildings, bridges, and most any other structure that
operates in the small strain linear elastic regime.

Small strain mechanics represent the 1st order linearization of
finite deformation nonlinear mechanics. Of course, small strain mechanics will not
yield accurate quantitative predictions in nonlinear problems. But they
can provide excellent qualitative insights and understanding of complex
nonlinear processes.

The section begins with basic definitions of stress and strain, then moves to
principal values, and concludes with Hooke's Law.
Keep in mind that all topics covered here are in the context of small strains,
deformations, displacements, rotations, etc.