3. (a) Use method of joints to determine forces in all members (all distances are in mm) (b) Find the resultant force at the pin support and state its angle of inclination FIGURE 2 2400 3.3 kN 6 3.6 ky 12 2 + 2400 0.7 kN + 2400 3.3kN + 2400

For the beam shown: (a) determine the distance a for which the maximum positive and negative bending moments in the beam are equal; and (b) draw the corresponding shear and bending moment diagrams for the beam.

Refer to Figure P6.4. A strip load of q = 900 lb/ft2 is applied over a width B = 36 ft. Determine the increase in vertical stress at point A located z = 15 ft below the surface. Given: x = 27 ft. Figure P6.4