MCQ
If the length of the pendulum in pendulum clock increases by $0.1\, \%$, then the error in time per day is: (in $s$)
- A$86.4$
- B$4.32$
- ✓$43.2$
- D$8.64$
✓
Answer
Correct option: C.
$43.2$
c
${T}=2 \pi \sqrt{\frac{\ell}{g}}$
${T}=2 \pi \sqrt{\frac{\ell}{g}}$
$\frac{\Delta {T}}{{T}}=\frac{1}{2} \frac{\Delta \ell}{\ell}$
$\Delta {T}=\frac{1}{2} \times \frac{0.1}{100} \times 24 \times 3600$
$\Delta {T}=43.2$
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