Hey guys. Just signed up hear after finding the website. I really need some help on Mechanical Principles as i have just been handed work to do once i came back from my car crash. I dont have a clue what any of it means so i could really do with your help. One of the questions is: A steel bar of 70mm dia is subjected to a pull of 120kN. If E=200GN/m2 and the length is 400mm, calculate: a) the tensile stress b) the tensile straing c) the extension Any help at all would be appreciated.