The bottom chord AB in a small truss ABC (see figure) is fabricated from a W8 × 28 wide-flange steel section. The cross-sectional area A = 8.25 in.2 (Appendix E, Table E-1 (a)) and each of the three applied loads P = 45 k. First, find member force NAB; then, determine the normal and shear stresses acting on all faces of stress elements located in the web of member AB and oriented at (a) an angle θ = 0°, (b) an angle θ = 30°, and (c) an angle θ = 45°. In each case, show the stresses on a sketch of a properly oriented element.

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P = 45 kips 9 ft 12 ft By Ay NAB NAB