The plate has a hole centered across the width. The stress concentration factor for a flat bar under axial loading with a centric hole is
where r is the radius of the hole and D is the width of the bar. Write a computer program to determine the allowable load P for the given values of r, D, the thickness t of the bar, and the allowable stress σall of the material. Knowing that t = 1/4 in., D = 3.0 in. and σall = 16 ksi, determine the allowable load P for values of r from 0.125 in. to 0.75 in., using 0.125 in. increments.