I'm reading Feynman Lectures on Physics Volume 2 Chapter 39 on elastic materials. Equation 39.22 relates the elements in the elasticity tensor to the Young's modulus and the Poisson's ratio. I have no clue on how to get these relations myself.(adsbygoogle = window.adsbygoogle || []).push({});

For example, for C_xxxx, I think it should tell how the material is elongated in the x-direction in response to a stress in the x-direction. Hence I would suppose C_xxxx is just the Young's modulus Y, because this relation is just like F / A = Y * (delta l) / l.

Please kindly show me directions of how to derive these relations. You can find a copy of Feynman Lectures Vol 2 Ch 39 in http://student.fizika.org/~jsisko/K...n Physics/Vol 2 Ch 39 - Elastic Materials.pdf

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# Feynman lectures - elastic materials - eqn 39.22

Can you offer guidance or do you also need help?

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