Problem 1: In the figure below a solid bar with a 1.00 in diameter is subjected to a bending moment M and a twisting moment T. Given that the magnitude of the twisting moment and the bending moment are equal, so that M = T, answer the following questions: a) If the bar is made from a material that undergoes brittle failure under a tensile stress of 6000 psi, what is the value of the minimum moment that would produce brittle failure? Make a sketch of the bar; then determine and show the direction of the fracture plane with respect to the axial direction of the bar. Draw Mohr's circle and show your work. b) If the bar is made from a ductile material that yields plastically at a stress of 36000 psi, what is the value of the minimum moment that would produce yielding? Use von-Mises theory.

Problem 1: In the figure below a solid bar with a 1.00 in diameter is subjected to a bending moment M and a twisting moment T. Given that the magnitude of the twisting moment and the bending moment are equal, so that M = T, answer the following questions: a) If the bar is made from a material that undergoes brittle failure under a tensile stress of 6000 psi, what is the value of the minimum moment that would produce brittle failure? Make a sketch of the bar; then determine and show the direction of the fracture plane with respect to the axial direction of the bar. Draw Mohr's circle and show your work. b) If the bar is made from a ductile material that yields plastically at a stress of 36000 psi, what is the value of the minimum moment that would produce yielding? Use von-Mises theory.

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 3.3.5P: A prospector uses a hand-powered winch (see figure) to raise a bucket of ore in his mine shaft. The...

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