In the figure below, two elastic members AB and CD are of rectangular cross section and have the same cross-sectional area A. They are made of the same material with Young's modulus E. They are pined to a ceiling at the top and to a rigid member BDE at the bottom. 1) The longitudinal force in member CD is a) 0 b) P (tensile) c) 2P (tensile) d) P (compressive) e) 2P (compressive) 2) The longitudinal force in member AB is a) 0 b) P (tensile) c) 2P (tensile) d) P (compressive) e) 2P (compressive) 3) The tensile stress o, in member CD is a) 0 b) P/A c) 2P/A d)-P/A e) -2P/A 4) The tensile stress o, in member AB is b) P/A a) 0 c) 2P/A 5) The tensile strain & in member CD is a) 0 b) PE/A c) 2P/AE 10) The tensile stress o, is a) 60 MPa d)-50 MPa P 11) The shear stress my is a) 60 MPa d) -50 MPa d) -PE/A 6) The displacement of point B in the positive x-direction is b) -PE/AL a) 0 c) PL/AE d) -PL/AE b) -60 MPa c) 50 MPa e) 20 MPa X 7) The displacement of point E in the positive x-direction is a) PE/AL b) PL/AE c) 3PL/AE d) 3PE/AL in member CD is c) 2P/A E b) -60 MPa c) 50 MPa e) 20 MPa rigid d) -P/A b) P/A d) -P/A e) -2P/A 8) The maximum shear stress a) P/L Questions 9 through 11 (3 points each): refer to the stress state shown to the right 9) The tensile stress o, is a) 60 MPa d)-50 MPa 20 MPa b) -60 MPa c) 50 MPa e) 20 MPa A.E e) -2P/A e) -2P/AE e) -2PL/AE e) 5PL/AE 60 MPa 50 MPa Questions 12 through 16 (3 points each): Use the stress-strain curve of a tensile specimen as shown below. O (MPa) 80 60 40 20 0 0 12) The yield stress is a) 30 MPa TE 0.002 0.004 0.006 0.008 0.01 0.012 b) 50 MPa 13) The ultimate tensile stress is a) 30 MPa b) 50 MPa 14) The Young's modulus is a) 50 MPa b) 70 MPa c) 60 MPa c) 60 MPa 17) The displacement & is a) PL/AE c) PA/L E e) 0 18) The displacement & is a) PL/AE c) PAE/L e) 0 d) 70 MPa b) PAE/L d) PL/AE1 + PL/A2E2 d) 70 MPa b) PL/AE2 d) PL/AE + PL/AE2 c) 6 GPa d) 11.7 GPa 15) If the specimen is loaded to a stress of 65 MPa and then strain is approximately a) 0 e) 0.01 b) 0.0015 c) 0.004 d) 0.008 16) If the diameter of the unloaded specimen is 1cm and the Poisson ratio of the material is V= = 0.3, what is the specimen diameter just prior of yield of the tensile specimen? a) 0.3cm b) 0.7cm c) 0.9994 cm d) 1.0006cm e) 1.3cm e) 80 MPa Questions 17 through 22 (4 points each): Two rectangular bars of length I are welded together. Bar AB has cross-sectional area A and Young's modulus E. Bar BC has cross- sectional area A2 and Young's modulus E2. Answer the questions for the various constraints and loadings shown. e) 80 MPa A e) 25 GPa unloaded, the residual plastic A P B A2, E2 L L Questions 17 and 18: Force P at point B and no displacement at A 19) The displacement a) QL/AE c) QA/L E & is b) QAE/L d) QL/AE + QL/A2E2 20) The displacement & is a) QL/AE c) QAE/L b) QL/AE2 d) QL/AE + QL/A2E2 21) The tensile force in member BC is a) 0 c) P/2 e) P/(AE+1) b) P d) PA2E2/(AE+AE2) 22) The displacement dis a) 0 c) PL/2A2E2 e) PL/[A2E2(A1E+1)] b) PL/AE2 d) PL/(AE1+AE2) A A,E A L Questions 19 and 20: Force Qat point C and no displacement at A A,E A Questions 23 through 28 (4 points each): The two cylindrical member shown below are welded together and constrained against rotation at point A. They are both of length L. Member AB has radius r, polar moment of inertia J, and shear modulus G. Member BC has radius 12, polar moment of inertia J2, and shear modulus G. Axial torques TB and Tc are applied as shown. 23) The internal torque supported by member AB is a) 0 b) TB c) Tc 24) The internal torque supported by member BC is a) 0 b) TB c) Tc 25) The maximum shear stress in member AB is a) 0 b) TBr/J c) Tc ri/Ji d) (TB - Tc) r1/J1 26) The shear stress at the centerline (on the axis) of member AB is c) Tc ri/J d) (TB - Tc) r1/J1 27) In the case that Tc=0, the maximum shear stress in member BC is c) TB 12/J d) T r/(J+J) a) 0 b) TBr1/J a) 0 b) TBr1/J 28) The twist at point B is a) 0 b) TBL/J1G 29) The twist c at point C is a) Tc L/JG2 d) TB L/J1G+ Tc L/JG2 d) TB-TC P+ , J , G d) TB-TC B B L L Questions 21 and 22: Force P at point B and no displacement at A and C TB. B B c) Tc L/JIG d) (TB - Tc) L/J1G b) (TB-Tc) L/J2G2 e) (TB + Tc) L/J1G1+ Tc L/J2G2 B e) TB + TC A2, E2 e) TB + TC L 2845 A2, E2 r2, J, G C Tc,Oc e) 2TB r2/J e) (TB + TC) r/J e) (TB + Tc) r/J1 e) (TB + Tc) L/JG c) (TB + Tc) L/JG2