2) steel rod (1) is fastened to brass rod (2) with a pin at b. the diameter of the pin is 7 /8 in. both rods are fixed at their ends a and c. the cross-sectional area of the steel rod is 1 in2 and the brass rod 1.5 in2 . the coefficient of thermal expansion for the steel is 6.5 x 10-6 /°f and its elastic modulus is 29 x 103 ksi. the coefficient of thermal expansion for the brass is 11.3 x 10-6 /°f and its elastic modulus is 15 x 103 ksi. a) the temperature drops 40°f. write the equilibrium and compatibility equation(s) needed to solve the problem along with supporting sketches. b) calculate the internal force in members (1) and (2) in kips. indicate tension or compression. [ans. to check: f1 = 9.2 k] c) calculate the average normal stress in each member in ksi. indicate tension or compression. d) compute the shear stress in the pin at b in ksi. [ans. to check: τ = 15.3 ksi] e) calculate the movement at b in inches. clearly indicate direction.