A hollow steel tube used in a roof structure has an outer diameter, d; = 104 mm and inner diameter, d2 = 82 mm. The length of the tube is given by L = 2.75 m and has shear modulus, G = 28 GPa. If the tube is twisted in pure torsion by torques acting at the ends, distinguish the angle of twist when the maximum shear stress, Tmax = 48 MPa.

6- A circular shaft is composed of a steel core and a brass covering, as shown in the figure. Under the applied torque, what is the maximum shear stress in each material? The composite shaft is attached to a wall at A. B O T= 5 KN•m Steel core r=15mm G=78 GPa bross cylinder ro=20mm (outer diameter) G=39 GPa

When an axial load is applied to the ends of the bar shown in the figure, the total elongation of the bar between joints A and C is 0.18 in. In segment (2), the normal strain is measured as 1,650 pin/in. Assume L₁ - 34 in. and L₂-83 in. Determine (a) the elongation of segment (2). (b) the normal strain in segment (1) of the bar. (1) Answers: (a) in.& (b) = 4 i B (2) 4₂ in, pin/in.