[Young's modulus for copper and steel are $1 \times 10^{11} N / m ^2$ and $2 \times 10^{11} N / m ^2$ respectively]
| 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 |
