The beams shown in the figure are subjected to bending moments M= 250 Nm. Each beam has a rectangular cross section with height h = 44 mm and width b = 10 mm (perpendicular to the plane of the figure).
(a) For the beam with a hole at midheight, determine the maximum stresses for hole diameters d = 10, 16, 22, and 28 mm.
(b) For the beam with two identical notches (inside height h1= 40 mm), determine the maximum stresses for notch radii R = 2, 4, 6, and 8 mm.