6. A 2.5 in.-diameter steel propeller shaft of a boat transmits 2800 hp @ 1800 rpm. Bending and axial loads are negligible. Clearly draw and label necessary schematic diagrams and list necessary assumptions. (a) What is the shear stress at the surface of shaft? (b) If a hollow shaft of inside diameter 0.88 times outside diameter is used, what outside diameter would be required to give the same outer surface stress? (c) Compare weights of the solid and hollow shafts. What is % saving in weight of shaft material if hollow shaft is used? (d) As a design engineer, what important lesson have you learned from solving this this? (e) What is Polar Moment of Inertia?

6. A 2.5 in.-diameter steel propeller shaft of a boat transmits 2800 hp @ 1800 rpm. Bending and axial loads are negligible. Clearly draw and label necessary schematic diagrams and list necessary assumptions. (a) What is the shear stress at the surface of shaft? (b) If a hollow shaft of inside diameter 0.88 times outside diameter is used, what outside diameter would be required to give the same outer surface stress? (c) Compare weights of the solid and hollow shafts. What is % saving in weight of shaft material if hollow shaft is used? (d) As a design engineer, what important lesson have you learned from solving this this? (e) What is Polar Moment of Inertia?

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 3.7.5P: The propeller shaft of a large ship has an outside diameter 18 in. and inside diameter 12 in,, as...

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