P8.90 The grooved shaft shown in Figure P8.90 is made of C86100 bronze (see Appendix for properties). The major shaft diameter is D = 50 mm, the minor shaft diameter at the groove is d = 34 mm, and the radius of the groove is r= 4 mm. Determine the maximum allowable moment M that may be applied to the shaft if a factor of safety of 1.5 with respect to failure by yield is specified. M D -Radius r FIGURE P8.90 M