The Yeoh hyperelastic solid constitutive model.[^1]
**Parameters**
- The bulk modulus $`\kappa`$.
- The shear modulus $`\mu`$.
- The extra moduli $`\mu_n`$ for $`n=2\ldots N`$.
**External variables**
- The deformation gradient $`\mathbf{F}`$.
**Internal variables**
- None.
**Notes**
- The Yeoh model reduces to the [Neo-Hookean model](super::NeoHookean) when $`\mu_n\to 0`$ for $`n=2\ldots N`$.