QUESTION 3 A steel bar AD has a cross-sectional area of 260 mm² is illustrated in Figure Q3. The steel bar is loaded by forces P = 12 kN, P2 = 8 kN, and P3 = 6 kN. a) Determine the axial stress in section AB. (2 marks) b) Assuming that the modulus of elasticity E = 210 GPa, calculate the change in length (8) of the bar. (4 marks) c) Determine the new value of load P3 to be applied in the same direction so that the steel bar does not change in length when all three loads are applied. (4 marks) P1 P2 P3 A В С 1.5 m 0.6 m 0.9 m

QUESTION 3 A steel bar AD has a cross-sectional area of 260 mm² is illustrated in Figure Q3. The steel bar is loaded by forces P = 12 kN, P2 = 8 kN, and P3 = 6 kN. a) Determine the axial stress in section AB. (2 marks) b) Assuming that the modulus of elasticity E = 210 GPa, calculate the change in length (8) of the bar. (4 marks) c) Determine the new value of load P3 to be applied in the same direction so that the steel bar does not change in length when all three loads are applied. (4 marks) P1 P2 P3 A В С 1.5 m 0.6 m 0.9 m

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 2.4.6P: Three prismatic bars, two of material A and one of material B. transmit a tensile load P (see...

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