Figure 7. Comparison of the natural frequencies obtained for the cantilever beam with a transverse Figure 7. Comparison of the natural frequencies obtained for the cantilever beam with a transverse Figure 7. Comparison of the natural frequencies obtained for the cantilever beam with a transverse closed crack that has the parameters x = 604 mm and a = 1 mm. closed crack that has the parameters x = 604 mm and a = 1 mm. closed crack that has the parameters x = 604 mm and a = 1 mm.