Material Elastic Modulus, GPa Yield Strength, MPa Tensile Strength, MPa Copper Aluminum 110 248 289 70 255 420 alloy Steel 207 448 551 Brass alloy 101 345 420

A steel bar with a length of 3 m, diameter of 25 mm, modulus of elasticity of 207 GPa, and linear coefficient of thermal expansion of 0.000009 m/m/°C is fixed at both ends when the ambient temperature is 40°C. If the ambient temperature is decreased to 15°C, what internal stress will develop due to this temperature change? Is this stress tension or compression? Why?

A cylindrical rod with a length of 380 mm and a diameter of 10 mm is to be subjected to a tensile load. The rod must not experience plastic deformation or an increase in length of more than 0.9 mm when a load of 24.5 kN is applied. Which of the four materials listed in table are possible candidates? Justify your answer. Material Elastic Modulus, GPa Yield Strength, MPa Tensile Strength, MPa 110 ETT 70 207 101 Copper Aluminum alloy Steel Brass alloy 248 255 448 345 289 420 551 420 * Plastic deformation is defined as a process in which the object due to applied force changes its size or shape in a way that is not reversible