4 Consider a single crystal of nickel oriented such that a tensile stress is applied along a [001] direc- tion. If slip occurs on a (111) plane and in a [101] direction and is initiated at an applied tensile stress of 13.9 MPa (2020 psi), compute the critical resolved shear stress.

*9-72. The cylinder CD af the assembly is heated from T, = 30 °C to T, = 180 °C using electrical resistance. At the lower temperature T, the gap between C and the rigid bar is 0.7 mm. Determine the force in rods AB and EF caused by the increase in temperature. Rods AB and EF are made of steel, and cach has a cross-sectional area of 125 mm. CD is made of aluminum and has a cross-sectional area of 375 mm. E = 200 GPa, Ea = 70 GPa, and au = 23(10)/C a7 mm ல் mm 300் m

7-71. An air-filled rubber ball has a diameter of 150 mm. If the air pressure within it is increased until the ball's diameter becomes 175 mm, determine the average normal strain in the rubber. 200 mm 200 mm 300 mm -300 mm- 200 mm н

7-18. The shaft is supported at its ends by two bearings A and B and is subjected to the forces applied to the pulleys fixed to the shaft. Determine the resultant internal loadings acting on the cross section at point C. The 400-N forces act in the -z direction and the 200-N and 80-N forces act in the +y direction. The journal bearings at A and B exert only y and z components of force on the shaft. X A 200 mm 300 mm 200 mm 400 N 150 mm 150 mm 400 N D 400 mm 200 N Prob. 7-18 B 200 N Z 80 N 80 N y