MCQ
A particle is tied to $20\, cm$ long string. It performs circular motion in vertical plane. What is the angular speed of particle 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
$m r w^{2}=m g$
$m r w^{2}=m g$
$w=\sqrt{\frac{g}{r}}=\sqrt{\frac{9.8}{0.2}}=7 \mathrm{rad} / \mathrm{sec}$
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