Q. A cane filled with water is revolved in a vertical circle of radius $4\ m$ and the water just does not fall down. The time period of revolution will be
A) $1\ sec$
B) $10\ sec$
C) $8\ sec$
D) $4\ sec$
Explanation
(d) For critical condition at the highest point $\omega = \sqrt{g/R}$
$\Rightarrow T = \frac{2\pi}{\omega} = 2\pi\sqrt{R/g} = 2 \times 3.14\sqrt{4/9.8} = 4\ sec$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.