Question:
A steel rod of length $1 \mathrm{~m}$ rests on a smooth horizontal base. If it is heated from $0^{\circ} \mathrm{C}$ to $100^{\circ} \mathrm{C}$, what is the longitudinal strain developed?
Solution:
Since, there is no opposition in expansion of length, no stress develops and hence no longitudinal strain developed.