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Next, expand sizing under "Details of "Mesh"" if it is not already expanded. Finally, change the element size to 2 meters and click enter. The total length of the bar is 4 meters, and the element size was set to 2 m, thus the mesh will be composed of two elements. (On a side note, if ten elements were desired, then the element size would be set to 4m/10=0.4m.) Then, click on Update, . At this point you should see, a similar image to the one below.
The mesh has now been set and the model window can be closed.