Question 4 A steel rod of 20 mm diameter passes centrally through a copper tube of 50 mm external diameter
and 40 mm internal diameter. The tube is closed at each end by rigid plates of negligible thickness.
The nuts are tightened lightly home on the projecting parts of the rod. If the temperature of the
assembly is raised by 50°C, calculate the stresses developed in copper and steel. Take E for steel
and copper as 200 GN/m² and 100 GN/m² and α for steel and copper as 12x 10-6
per °C and 18 x
10-6
per °C