Prob: 2 a cylindrical specimen of aluminum having a diameter of 0.505 in. (12.8 mm) and a gauge length of 2.000 in. (50.800 mm) is pulled in tension. use the load–elongation characteristics tabulated below and (a) plot the data as engineering stress versus engineering strain. (b) compute the modulus of elasticity. (c) determine the yield strength at a strain offset of 0.002. (d) determine the tensile strength of this alloy. (e) what is the (approximate) ductility, in percent elongation? (f) populate that data with corresponding true stress and strain values (g) compute the strain hardening exponent by using the equation

Aloaded platform of total mass 500 kg is supported by a dashpot and by a set of springs of effective stiffness 72 kn/m. it is observed that when the platform is depressed through a distance x = 12.5 cm below its equilibrium position and then released without any initial velocity; it reaches its equilibrium position in the shortest possible time without overshoot. find the position and velocity of the loaded platform 0.10 sec. after its release. if a further load of 400 kg is added to the platform, find, i) the frequency of damped vibrations, and i) the amplitude of vibration after 2 complete oscillations, given that the initial amplitude is 15 cm.