A modal analysis determines the vibration characteristics such as natural frequencies and mode shapes of a structure; it serves as a starting point for several linear dynamic analyses. The mode frequencies and shapes depend on the distribution of mass and stiffness in the structure. In a stressed state the stiffness changes due to the stress stiffening, altering its vibration characteristics. In this video, you will see how to perform a prestressed modal analysis in Ansys Workbench. Additionally, you will see how different natures of stress (tension and compression) change the frequency.