Choose the correct relationship between Poisson ratio (σ) , bulk...

The relations of Young's modulus, $Y$, bulk modulus, $K$, the modulus of rigidity, $η and Poisson's ratio,$\sigma$are given as</p><p>$Y = 3K ( 1 - 2\sigma ) \ldots \left(1\right)$and </p><p>$Y = 2η\left(1 + \sigma\right) \ldots \left(2\right)$</p><p>From equation \left(1\right)and\left(2\right)$, we have

$⇒ 2η\left(1 + \sigma\right) = 3K\left(1 - 2\sigma\right)$

$⇒ \sigma = \left(\dfrac{3K - 2η}{6K + 2η}\right)$