A cross section of a beam is shown. For any moment M, which surface of the cross section will have the greater bending stress magnitude (either tension or compression)? a. BOTTOM SURFACE b. TOP SURFACE

Mohr's circle is shown for a point in a physical object that is subjected to plane stress. Each grid square is 220 psi in size. (a) Determine the stresses Ox, Oy, and the magnitude of Txy and show them on a stress element. (b) Determine the principal stresses and the magnitude of the maximum in-plane shear stress acting at the point and show these stresses on an appropriate sketch (e.g., see Figure 12.15 or Figure 12.16). Answer: (a) ox= i Oy = Txy = i i (b) Op1 = i op2 = i max in-plane y i C psi psi psi X psi psi psi σ

Below two stress strain curves are drawn to scale. Explain the advantage/disadvantage of material A vs. B.

Mohr’s circle is shown for a point in a physical object that is subjected to plane stress. Each grid square is 600 psi in size. (a) Determine the stresses σx, σy, and the magnitude of τxy and show them on a stress element. (b) Determine the principal stresses and the magnitude of the maximum in-plane shear stress acting at the point and show these stresses on an appropriate sketch (e.g., see Figure 12.15 or Figure 12.16).