
For a perfectly rigid body, the elasticity is:
1. unity
2. zero
3. infinite
4. indeterminate
Which of the following expressions correctly relates Poisson’s ratio \(\sigma,\) bulk modulus \(B,\) and modulus of rigidity \(G\)?
1. \(\mathit{\sigma}{=}\dfrac{{3}{B}{-}{2}{G}}{{2}{G}{+}{6}{B}}\)
2. \(\mathit{\sigma}{=}\dfrac{{6}{B}{+}{2}{G}}{{3}{B}{-}{2}{G}}\)
3. \(\mathit{\sigma}{=}\dfrac{9BG}{{3}{B}{+}{G}}\)
4. \({B}{=}\dfrac{{3}\mathit{\sigma}{-}{3}{G}}{{6}\mathit{\sigma}{+}{2}{G}}\)
Select the incorrect definition:
| 1. | Deforming Force: A force that changes the configuration of a body. |
| 2. | Elasticity: The property of regaining the original configuration. |
| 3. | Plastic body: A body that can be easily melted. |
| 4. | Elastic limit: The point beyond which a material begins to flow. |