30. A compressive load P is transmitted through a rigid plate to three magnesium-alloy bars that are identical except that initially the middle bar is slightly shorter than the other bars (see figure). The dimensions and properties of the assembly are as follows: length L = 1.0 m, cross-sectional area of each bar A = 3000 mm2, modulus of elasticity E = 45 GPa, and the gap s = 1.0 mm. Calculate the downward displacement of the rigid plate when P = 400 kN in mm. A. 1.488 В. 1.321 С. 1.207 D. 1.579

30. A compressive load P is transmitted through a rigid plate to three magnesium-alloy bars that are identical except that initially the middle bar is slightly shorter than the other bars (see figure). The dimensions and properties of the assembly are as follows: length L = 1.0 m, cross-sectional area of each bar A = 3000 mm2, modulus of elasticity E = 45 GPa, and the gap s = 1.0 mm. Calculate the downward displacement of the rigid plate when P = 400 kN in mm. A. 1.488 В. 1.321 С. 1.207 D. 1.579

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter2: Axially Loaded Members

Section: Chapter Questions

Problem 2.7.10P: A compressive load P is transmitted through a rigid plate to three magnesium-alloy bars that are...

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