shear modulus, G young's modulus, E and Poisson's ratio, $v$:
$G=E/(1+2v)$
I have always wondered how this relation is derived, but have never found a derivation that I could follow online.
I assume it begins with drawing a distorted square and finding the change in distortion, but I haven't been able to successfully derive this myself. Can one of you lay out the steps for me, in all of the literature I own this equation is simply presented as is with no explanation. I am asking this question because I am currently studying the Finite Element method applied to elastostatics.
Thanks in advance.