Problem 4.1 The two-member pinned frame is subjected to the distributed loading shown. Member CB has a square tubular cross section with an outer edge dimension of 35 mm and an inner edge dimension of 30mm. Take w = 8 kN/m. a. Determine the average normal stress and average shear stress acting on section a-a. b. Determine the average normal stress and average shear stress acting on section b-b. If the pin at A is in double shear and has a diameter of 5mm, calculate the maximum average shear stress on the pin cross- C. section. 4 m b Section a-a outer: 35x35mm inner: 30x30mm JI Section b-b outer: 35x58.3mm inner: 30x50mm A 3 m B W