QUESTION 29 A cylindrical specimen of Titanium alloy of 10 mm diameter is subjected to a load of 20 kN along its axis. If the alloy has an elastic modulus of 110 GPa, how far can be extended elastically for a 1-meter length? (a) 0.381 mm (b) 2.316 mm (c) 7.60 mm (d) 11.3 mm QUESTION 30 Which one of the following statements is correct? (a) The material's resistance to plastic deformation is the stiffness of the material. (b) Toughness is the total area under the stress-strain curve of ductile materials. The strength of some metals can be significantly increased by plastic deformation. e Yield strength is the maximum stress a ductile material can carry before fracture. QUESTION 31 A solid bar of aluminium (E=70 GPa) has a square section of 10 mm x 10 mm and length of 500 mm. What is the final length of the bar if it is subjected to a load of 100 kN? (a) 500.715 mm. (b) 715 mm. (c) 142.85 mm. (d) 507.05 mm.l2 QUESTION 32 The rectangular plate is deformation into the shape of parallelogram shown by the dashed line in Figure 8. Determine the average shear strain M (in radians) at A using small strain analysis. 400 nunJ 3 Figure 8. Deformation of rectangular plate into the shape of parallelogram. 5 300 (a) (b) 4730 (c) % (d) 5 i 2 240 QUESTION 20 The differential manometer shown in figure 4 is used to measure pressure difference between pipe A and B. Pipe A is conveying water while pipe B is conveying air. If the pressure at B is 12kPa calculate the pressure at A. 1.2m 2.3m VB A Figure 4. 35 kPa 12 kPa 23 kPa 24 kPaQUESTION 34 A 200 mm long acrylic plastic rod of diameter 20 mm is subjected to an axial load, P (see Figure 10). If the material has Young's Modulus, E=2.70 GPa and Poisson's ratio, v=0.4, determine the change in diameter of the rod if the applied load is 450 N. P P 200 mm Figure 10. Acrylic plastic rod subjected to an axial load, P. 0.00424 mm 0.0167 mm 0.0034 mm 0.0252 mm END OF PAPER