A circular bar of magnesium alloy is 32 in long. Answer the following questions using the strain graph below.
(a) What is the proportional limit of the bar?
(b) What is the modulus of Elasticity of the bar?
(c) If the bar is loaded in tension to an elongation of 0.225 in and then the load is removed,
(i) What is the permanent set of the bar if any (the strain that remains in the bar after unloading) ?
(ii) If the bar is reloaded, what is the new proportional limit?
Show your answers graphically on the graph below and also clearly write the values.