A center cracked tension plate contains an initial through-the-thickness crack of length 2a = 1.2 inch. For the material, ys = 100 ksi and K = 60 ksi in. The plate width 2W = 2 inch and the thickness B = 0.3 inch. Assume plane stress conditions and the following stress intensity factor relationship. 2W If P = 18 kips, determine the effective SIF, Keff. Use the Irwin's model for the crack tip plastic zone size. (1 kip = 1,000 lb) 2W | 2a P