How to Calculate Poissons Ratio
What is Poissons Ratio?
Poisson's ratio (ν) = transverse strain / axial strain: ratio of shrinkage perpendicular to stress; typically 0.2-0.5.
Formula
Calculate Poisson\'s ratio: ν = (E-2G)/(2E)
- E
- E value — Variable used in the calculation
Step-by-Step Guide
- 1Input material properties: Young's modulus and shear modulus
- 2Calculate Poisson's ratio: ν = (E-2G)/(2E)
- 3Results show lateral deformation under load
Worked Examples
Input
Rubber: ν ≈ 0.5 (incompressible)
Result
Steel: ν ≈ 0.3 (some volume change)
Common Mistakes to Avoid
- ✕Confusing with strain/stress ratio
- ✕Not accounting for material nonlinearity
Frequently Asked Questions
Can Poisson's ratio exceed 0.5?
Theoretically no for isotropic materials (>0.5 = unphysical volume expansion).
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