MCQ
A particle is tied to $20\, cm$ long string. It performs circular motion in vertical plane. What is the angular velocity of string when the tension in the string at the top is zero ........ $rad/sec$
- A$5$
- B$2$
- C$7.5$
- ✓$7$
✓
Answer
Correct option: D.
$7$
d
$\omega = \sqrt {\frac{g}{r}} = \sqrt {\frac{{9.8}}{{0.2}}} = 7\,rad/\sec $
$\omega = \sqrt {\frac{g}{r}} = \sqrt {\frac{{9.8}}{{0.2}}} = 7\,rad/\sec $
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