Q.
A thin ring of an alloy of inner diameter $20 \,cm$ and cross-sectional area $1\, mm ^{2}$, is heated until it easily slides on a rigid cylinder of diameter $20.025\, cm$. When the ring cools down, the value of tension in it is found to be $a \times 10^{2} N$. Find the value of $a$.
(For alloy: $\left.\alpha=10^{-5} /{ }^{\circ} C , Y=400 \,GPa \right)$
Mechanical Properties of Solids
Solution: