Question:
A pendulum clock gives correct time at $20^{\circ} \mathrm{C}$ at a place where, $g=9.800 \mathrm{~m} / s^{2}$. The pendulum consists of a light steel rod connected to a heavy ball. It is taken to a different place where $\mathrm{g}=9.788 \mathrm{~m} / \mathrm{s}^{2}$. At what temperature will it give correct time? Coefficient of linear expansion of steel $=12^{\times 10^{-6} /{ }^{\circ} \mathrm{C}}$.
Solution: