Question

A rod of length $2\text{m}$ rests on smooth horizontal floor. If the rod is heated from $0^{\circ }C$ to ${20}^{\circ }C$. Find the longitudinal strain developed?

• A. ${10}^{-3}$
• B. $2\times {10}^{-3}$
• C. Zero
• D. None

Answer 1

The correct option is C Zero

We know that, when the rod is freely expanded, the stress produced is $0$.

In other words, there is no restriction in the expansion of the rod so no stress will be developed.

As
stress $\propto$ strain
so, strain $=0$.