ABSTRACT
IV. THE STRESS TENSOR lf one isolates a rectangular parallelepiped of material having infinitesimal dimensions such as shown in Figure 1.5, one finds that two kinds of forces act on the material element. These are body forces and surface forces. Body forces result from the action of external fields such as gravity: suiface forces express the inAuence of material outside the parallelepiped but adjacent to a given surface.
