Bundles of protein filaments inside tissue cells are structural elements that can generate contractile
force against the materials to which they adhere. Figure 3 shows struts called "stress fibers" that extend from one end of the cell to the other. These fibers are made of crosslinked, filamentous actin, with an average diameter of 2 µm and an effective "stiffness" E of 16 kN/m2.
If we assume the connections at either end of the stress fiber can be modeled as pins, how much force P,would the cell need to generate to buckle the longest of these stress fibers?