The engineer needs to design a cylinder shaft, with length L=1 m, to transmit a power of 500W and rotating at 17 rad/s. The radius of the cross-section is 0.01m, which gives us the polar 2nd moment of area J=1.57x10 m². Two materials can be chosen: Material A: expensive, shear modulus G-80GPa, and the maximum allowed shear stress is 280MPa Material B: cheap, shear modulus G=25GPa, and the maximum allowed shear stress is 200MPa (a) Determine the torsion angles if material A or B is applied, respectively. (b) If the safety MUST be ensured, and a lower cost is preferred, which material should be chosen? (Safety factor = 0.8)

The engineer needs to design a cylinder shaft, with length L=1 m, to transmit a power of 500W and rotating at 17 rad/s. The radius of the cross-section is 0.01m, which gives us the polar 2nd moment of area J=1.57x10 m². Two materials can be chosen: Material A: expensive, shear modulus G-80GPa, and the maximum allowed shear stress is 280MPa Material B: cheap, shear modulus G=25GPa, and the maximum allowed shear stress is 200MPa (a) Determine the torsion angles if material A or B is applied, respectively. (b) If the safety MUST be ensured, and a lower cost is preferred, which material should be chosen? (Safety factor = 0.8)

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 3.11.3P: A thin-walled aluminum tube of rectangular cross section (sec fig me) has a centerline dimensions b...

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