The Finite Element method is one of the most widely used methods by Engineers in the various areas of activity, especially Mechanical Engineering, to design or solve problems. However, the understanding of the method is not always easy to perform, since in the literature, when explaining the method, the examples are generic or presented quickly. Thus, this paper presents the solution of a problem involving a rocking beam (set), which is solved analytically and later by the finite element method. The comparison of the solutions found is established as reflection analysis. Elasticity theory, Ordinary Differential Equations and Finite Element Method are used to approximate the reader of the Finite Element Method, in a concise and objective, easy-to-understand reading performed with a reduced explanation. Comparing the method by means of a problem.