Given:
Under a certain applied torque, a thin-walled titanium
(G = 40 GPa) shaft of length L = 2 m, radius R = 80 mm, and thickness t = 5 mm, experiences an angle of twist of q = 5°.

Req'd:
Determine the shear stress in the shaft t.

Sol'n: First convert 5° to radians: q = 5° (p radians / 180°) = 0.0873 radians.

The shear strain is related to the angle of twist by:

g = Rq/L = (80 mm)(0.0873 radians) / 2000 mm = 0.00349