The rod is made of A-36 steel and has a diameter of 0.25 in and a length of 4 ft. Attached to each end of the rod is a spring which is fixed to a wall. If the springs are compressed 0.5 in. when the temperature of the rod is T=40 F, determine the force in the rod when its temperature is T=160 F. It is given that k=10,000 lb/in. Equations: F=kx, Thermal Deformation=alpha*change in temp*length Attempted Solution: Find the thermal deformation in the rod at T=160 F, then use this in F=kx to solve for F. I know the correct answer is 163 lbs, but I don't understand why.