The inner spring of a compound helical spring is arranged within and concentric with the outer one and is shorter by 9 mm. The outer spring has 10 coils with a mean diameter of 24 mm and a wire diameter of 3 mm. (a) Determine the stiffness of the inner spring when an axial load of 162 N causes the outer spring to compress by 16 mm. If the radial clearance between the springs is 1.5 mm and the inner spring has 8 coils, find its wire diameter. (c) Disregarding the effect of curvature, find the maximum shear stress in each of the spring. Given G = 78 GPa.

The inner spring of a compound helical spring is arranged within and concentric with the outer one and is shorter by 9 mm. The outer spring has 10 coils with a mean diameter of 24 mm and a wire diameter of 3 mm. (a) Determine the stiffness of the inner spring when an axial load of 162 N causes the outer spring to compress by 16 mm. If the radial clearance between the springs is 1.5 mm and the inner spring has 8 coils, find its wire diameter. (c) Disregarding the effect of curvature, find the maximum shear stress in each of the spring. Given G = 78 GPa.

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter11: Columns

Section: Chapter Questions

Problem 11.3.20P: The hoisting arrangement for lifting a large pipe is shown in the figure. The spreader is a steel...

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