A thin polymer plate PQR is deformed so that corner Q is displaced downward by a distance L = 1.45 mm to new position Q' as shown Determine the shear strain at Q' associated with the two edges (PQ and QR). 120 mm 480 mm 가 R 240 mm -2692 μrad O-3352 μrad -4917 prad -3610 prad Q 'Q' X

Narrow bars of aluminum are bonded to the two sides of a thick steel plate as shown. Initially, at T₁ = 70°F, all stresses are zero. Knowing that the temperature will be slowly raised to T₂ and then reduced to T₁, determine (a) the highest temperature T₂ that does not result in residual stresses, (b) the temperature T₂ that will result in a residual stress in the aluminum equal to 58 ksi. Assume aa = 12.8 x 10-6/°F for the aluminum and a = 6.5 × 10-6/°F for the steel. Further assume that the aluminum is elastoplastic with E = 10.9 × 106 psi and ay = 58 ksi. (Hint: Neglect the small stresses in the plate.) Fig. P2.121