by inspection the internal axial forces in regions AB, BC. and CD, are all constant yet have different magnitudes using the method of sections these loading are ditermined in fig. 1-16b and the nomal force diagram which represents these results graphically is shown in fig.1-16c by inspection the largest loading is in region BC where Pbc=30KN since the cross sectional area of the bar is constant the largest average nornal stress aslo occurs within this region of the bar