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STD 11 - 5. work,energy,power and collision — JEE STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceJEESTD 11 - 5. work,energy,power and collision4 Marks
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
(d)$\omega = \sqrt {\frac{g}{r}} = \sqrt {\frac{{9.8}}{{0.2}}} = 7\,rad/s$

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