$\Delta \ell=\frac{ F ( L / 2)}{ AY }=\frac{( AL \rho g )( L / 2)}{ AY }$
$=\left(\frac{1}{2}\right) \rho g L ^2 / Y$
| Column $-I$ | Column $-II$ |
|
$(a)$ Stress is proportional to strain. |
$(i)$ Elastic limit |
| $(b)$ When the load of the wire is removed, the body does regain its original dimension. | $(ii)$ Limit of pro-portionality |
| $(iii)$ Plastic deformation |

