Determine the Poissons Ratio:

In separate experiments, Young's Modulus and Rigidity Modulus of a material have been calculated as 120 GP_a and 50 GP_a respectively. Determine the Poisson's Ratio & Bulk Modulus of the material.

Solution

 Here, Young's Modulus, E = 120 GP_a.

Assume Poisson's ratio be v.

Rigidity Modulus, G = E / 2 (1 + v) = 50 GP_a

 (1 + v) =  E /2G =  120 /(2 × 50) = 1.2

 ∴         Poisson's Ratio, v = 1.2 - 1 = 0.2

Bulk Modulus,   K = E / (3 (1 - 2ν))

=120 / (3(1 - 2 × 0.2))

= 66.667 GP_a.