A high strength drill rod used for boring a hole in the earth has a diameter of 50 mm. The allowable shear stress in the steel is 120 MPa and the shear modulus is G=80 GPa 1. Determine the required length of the rod so that one end of the rod can be twisted 4° with respect to the other end without exceeding the allowable stress. 2. Determine the torsional stiffness in N.m. 3. Determine the allowable shear strain of the rod.

A high strength drill rod used for boring a hole in the earth has a diameter of 50 mm. The allowable shear stress in the steel is 120 MPa and the shear modulus is G=80 GPa 1. Determine the required length of the rod so that one end of the rod can be twisted 4° with respect to the other end without exceeding the allowable stress. 2. Determine the torsional stiffness in N.m. 3. Determine the allowable shear strain of the rod.

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 3.3.12P: A propeller shaft for a small yacht is made of a solid steel bar 104 mm in diameter. The allowable...

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