(a) A steel bolt 650 mm2 cross-sectional area passes centrally through a copper tube to 1200mm2 cross-sectional area. The tube is 500mm long and closed by rigid washers, which are fastened by the threads on the steel bolt. The nut is now tightened by ¼ of a turn. Evaluate the stress in the bolt and the tube if the pitch of thread is 3 mm. Take :
Es = 2.05 x 105 N/mm2
Ec = 1.1 x 105 N/mm2
(b) Differentiate between ductile and brittle materials. Name any five ductile and brittle materials.