JEE Mains · Physics · STD 11 - System of particles and rotational motion
- JEE Mains 2020
- Hard
- MCQ
A bead of mass \(m\) stays at point \(P ( a , b )\) on a wire bent in the shape of a parabola \(y=4 Cx ^{2}\) and rotating with angular speed \(\omega\) (see figure). The value of \(\omega\) is (neglect friction)

Pick an option to check your answer.
Answer & Solution
Correct Answer
(B) \(2 \sqrt{2 g C}\)
Step-by-step Solution
Detailed explanation
In rotating frame
\(mx \omega^{2} \cos \theta= mg \sin \theta\)
\(x \omega^{2}= g \tan \theta\)
\(x \omega^{2}= g \cdot \frac{ dy }{ dx }\)
\(x \omega^{2}= g \cdot(8 cx )\)
\(\omega^{2}=8 gc\)
\(\omega=2 \sqrt{2 gc }\)
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