⁵Recognize that there would be two components of traction acting on the plane of cut. Shear stress is neither of those components. For example, if traction on a plane whose normal is e_z is, t_(ez) = a_xe_x + a_ye_y + a_ze_z, then the normal stress σ_(ez) = a_z and the shear stress τ_(ez) = . See chapter 4 for more details.