Q. A stone of mass 2kg is tied to a string of length 0.5 m. If the breaking tension of the string is 900 N, then the maximum angular velocity, the stone can have in uniform circular motion is
A) $30\ rad\ s^{- 1}$
B) $20\ rad\ s^{- 1}$
C) $10\ rad\ s^{- 1}$
D) $25\ rad\ s^{- 1}$
Explanation
(a) Here, Mass of a stone, $m = 2kg$
Length of a string, $r = 0.5\ m$
Breaking tension, $T = 900\ N$
As $T = mr\omega^{2}$ or $\omega^{2} = \frac{T}{mr} = \frac{900}{2 \times 0.5} = 900$
$\omega = 30\ rad\ s^{- 1}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.