2) The internal loadings at a cross section through the 6-in diameter drive shaft of a turbine consists of an axial force of 2500 lb, a bending moment of 800 lb-ft, a shear force of 400 lb, and a torsional moment of 1500 lb-ft. Determine the principal stresses at point A and B. Also calculate the maximum in-plane shear stress at this point.

Fig: 1

Fig: 2