A drill rod with a diameter of 12 mm is made of high-strength steel alloy with a shear modulus of 80 GPa. The rod is to be subjected to a torque T. What is the minimum required length L of the rod so that the cross section at one end can be rotated 90⁰ with respect to the other end without exceeding an allowable shear stress of 300 MPa?

A drill rod with a diameter of 12 mm is made of high-strength steel alloy with a shear modulus of 80 GPa. The rod is to be subjected to a torque T. What is the minimum required length L of the rod so that the cross section at one end can be rotated 90⁰ with respect to the other end without exceeding an allowable shear stress of 300 MPa?

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter3: Torsion

Section: Chapter Questions

Problem 3.5.5P: A tubular bar with outside diameterd2= 4.0 in, is twisted by torques T = 70,0 kip-in. (see figure)....

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