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Question

The following results were obtained by means of a tensile test on a carbon steel specimen, having an original diameter of 33 mm and an original length of 50 mm (gauge length). At the limit of proportionality the load was 91 kN and the extension is 0.0443 mm. The load at an upper yield point was 105 kN and the maximum load recorded was 185 kN. When the two pieces were fitted together after fracture, the length was measured and determined as 70 mm. The neck diameter was 15 mm. 7.1 Draw a neat, labelled load/extension diagram to demonstrate the above information. Calculate the following: 7.2 The stress at the limit of proportionality 7.3 Young's modulus of elasticity for carbon steel 7.4 The maximum tensile stress in the specimen 7.5 The percentage elongation of the specimen 7.6 The percentage decrease in the cross section area