If moment Mx and axial force N are applied simultaneously, the strain-energy density resul...

If moment Mx and axial force N are applied simultaneously, the strain-energy density resulting from these two actions is

where  ω is given by Eq. 9.10 and ∈θθ is found from Eq. 9.3 with r = R. Using this expression for strain-energy density, derive Eq. 9.3 l.

 (9.10)

 (9.3)

 (9.31)