A rectangular beam with notches and a hole (see figure) has dimensions h = 5.5 in., h1= 5 in., and width b = 1.6 in. The beam is subjected to a bending moment M = 130 k-in., and the maximum allowable bending stress in the material (steel) is σmax = 42,000 psi.
(a) What is the smallest radius Rmin that should be used in the notches?
(b) What is the diameter dmax of the largest hole that should be drilled at the midheight of the beam?
