Question

A rod is subjected to a uni-axial load within linear elastic limit. When the change in the stress is 200 MPa, the change in the strain is 0.001. If the Poisson's ratio of the rod is 0.3, the modulus of rigidity (in GPa) is

• A. 76.923

Answer 1

The correct option is A 76.923
With in linear elastic limit

$\sigma =Eϵ$

$E\to slopeof\sigma vsϵcurve$

$E=\frac{d\sigma }{dϵ}=\frac{200}{0.001}=200GPa$

$E=2G(1+\mu )$

$G=\frac{E}{2(1+\mu )}=\frac{200}{2(1+0.3)}=\frac{100}{1.3}$

= 76.9230GPa