Q. A body crosses the topmost point of a vertical circle with critical speed. Its centripetal acceleration, when the string is horizontal will be
A) $6\ g$
B) $3\ g$
C) $2\ g$
D) $g$
Explanation
(b) $v = \sqrt{3gr}$ and $a = \frac{v^{2}}{r} = \frac{3gr}{r} = 3g$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.