Use Hooke’s law to calculate the strain in the test section at the yield stress of 1018 carbon steel (σy= 370 MPa, E=200 GPa) and 6061-T6 Al (σy=275 MPa, E = 70 GPa). For an ASTM tensile specimen gauge length Lo= 50 mm and test section diameter Do is related to gauge length by the ratio Lo/Do = 4. Calculate the load at yield and the extension of the gauge length at yield. For an over-simplified comparison of strain and stress in longitudinal acoustic waves, assume that a longitudinal ultrasonic wave causes a maximum surface deflection of 0.1nm. Calculate the equivalent strain in a 50mm gauge length and equivalent tensile load for steel and aluminum specimens as above.