An engineering drawing marked with the dimensions used to machine the sample from a rectangular block of material. The length of the central portion of the sample is 50.00 mm having a width of 8.00 mm. A 45% ridge with a height of 1.50 mm at each end of the central portion extends the length of this section to 53.00 mm and the width to 11.0 mm. Each end of the sample has a threaded section of 15.00 mm. The width between the 50.00 mm central portion and the start of the threaded section is 10.00 mm.

Ridge detail: angled at 45 degrees to a point at the top and bottom of the sample, having a height of 1.50 mm and width of 2.91 mm. In Question 2a you are asked to calculate the stress acting on parts of a sample at the beginning and end of an experiment similar to that in Week 17. The load applied in the experiment was 4.51 kN.

All your answers to Question 2a should be given in appropriate units.

a.

i.To calculate the stress on the sample due to the applied tensile load you need to know the area over which this force is acting. Using information from Figure 2, calculate the relevant cross-sectional area of the sample within the gauge length at the start of the experiment in mm2 to 3 significant figures.