material is E. The axial displacement of the bar is u(x). The bar is fixed at both ends, i.e., u(0) = u(L) = 0. It can be shown that (you do not have to show it) the governing equilibrium equation is du AE- + f (x) = 0 dx2 with the boundary conditions u(0) = u(L) = 0. Now, let's suppose A = 0.1 m, L = 10 m, E = and f(x) = 1000 N/m. 200 GPa, f(x) * L