Question

A clock with a metal pendulum beating seconds keeps correct time at 0⁰C. If it loses 12.5 seconds a day at 25⁰C, the coefficient of linear expansion of metal of pendulum is

• A. $\frac{1}{86400}per^{o}C$
• B. $\frac{1}{43200}per{^\circ}C$
• C. $\frac{1}{14400}per{^\circ}C$
• D. $\frac{1}{28800}per{^\circ}C$

Answer 1

Answer: (A)

$\frac{1}{86400}per^{o}C$

Answer 2

Loss of time due to heating a pendulum is given as

∆T = $\frac{1}{2}\alpha\Delta\theta T$ ⇒ 12.5 = $\frac{1}{2} \times \alpha \times (25 - 0){^\circ}C \times 86400$

⇒ α$= \frac{1}{86400}per{^\circ}C$