3) [5 marks] Thermal expansion/contraction At 20 C room temperature, a Nickel pin (cylinder) has a diameter of 10.025 mm and a Tungsten bar has a 10.010 mm diameter axial hole. You are ask to press fit the pin into the bar by cooling the two parts to a low enough temperature at which the pin diameter is equal to the hole diameter. a) At what temperature different from room temperature are the diameters of the two components equal? b) Assume the Ni material of the pin yields at 345 MPa. Does it yield after being fitted into the Tungsten bar and heated back to room temperature? Give a stress estimation and explain your reasoning