I need this example solved but without having a sigma in the Y direction, σy=0, and σx=20 in tension instead of compression. Tau stays the same. τxy=60 MPa.
EXAMPLE
The state of plane stress at a point on a solid is represented on the element shown in the figure. Determine a) principal stresses, and b) the maximum in-plane shear stress and associated average normal stress.
σx = -20 MPa, σy = 90 MPa, τxy = 60 MPa.