MCQ
The length of a seconds pendulum is .... $cm$
- A$99.8$
- ✓$99$
- C$100$
- DNone of these
✓
Answer
Correct option: B.
$99$
b
(b )$T = 2\pi \sqrt {l/g} $
(b )$T = 2\pi \sqrt {l/g} $
$\Rightarrow l = \frac{{g{T^2}}}{{4{\pi ^2}}} = \frac{{9.8 \times 4}}{{4 \times {\pi ^2}}} = 99\;cm$
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