Q. A ball of mass$(m)0.5$ kg is attached to the end of a string having length $(L)$ 0.5 m. The ball is rotated on a horizontal circular path about vertical axis. The maximum tension that the string can bear is 324 N. The maximum possible value of angular velocity of ball (in rad/s) is

A) 9
B) 18
C) 27
D) 36
Explanation

(d) $T\cos\theta$ component will cancel $mg.$
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$T\sin\theta$ Component will provide necessary centripetal force the ball towards center C.
$\therefore T\sin{\theta = mr\omega^{2} = m(l\sin{\theta)\omega^{2}}\ }$
$or\ T = ml\omega^{2} \Longrightarrow \omega = \sqrt{\frac{T}{ml}}rad/s\ $
${or\ \omega}_{\max} = \sqrt{\frac{T_{\max}}{ml} = \sqrt{\frac{324}{0.5 \times 0.5} = 36\ rad/s}}$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.