minimum allowable design diameter

Question

A solid circular shaft needs to be designed to transmit a torque of 50N.m. If the allowable shear stress of the material is 140MPa, assuming a factor of safety of 2, the minimum allowable design diameter in mm.

(a) 8              (b) 16             (c) 24                (d) 32

Answer 1

Given a solid circular shaft to transmit a torque of 50N.m, the minimum allowable design diameter is