For each of the plane stress states listed below, draw a Mohr’s circle diagram properly labeled, find the principal normal and shear stresses, and determine the angle from the x axis to σ1. Draw stress elements as in Fig. 3–11c and d and label all details.
(a) σx = 12, σy = 6, τx y = 4 cw
(b) σx = 16, σy = 9, τx y = 5 ccw
(c) σx = 10, σy = 24, τx y = 6 ccw
(d) σx = 9, σy = 19, τx y = 8 cw