14.8 A beam with the cross section shown is acted on by a bending moment of 10,000 lb-in. Determine (a) the maximum tensile and compressive bending stress, and (b) the bending stress 1 in. from the bottom of the beam. 0.25 in. 0.25 in. -3 in.- PROB. 14.8 -0.25 in. 3 in. 14.7 What bending moment will cause a maximum bend- ing stress of 10,000 psi in the beam with the cross sec- tion shown? 0.25 in. 0.5 in. 3 in. 0.25 in. 0.5 in. 2 in. PROB. 14.7