Strain gauges mounted on a free surface of a piece of steel (E = 205 GPa, υ = 0.29) indicate strains of εx = -0.00042, εy = 0.00071, and γ xy = 0.00037.
A. Calculate the principal strains.
B. Use Hooke's laws to ?nd the principal stresses from the principal stresses.
C. Calculate σx, σy, and τ xy directly from εx, εy, and γ xy.
D. Calculate the principal stresses directly from σx, σy, and τ xy and compare your answers with the answers to B.