Question

A boy whirls a stone in a horizontal circle of radius 1.5 m and at height 2.0 m above level ground. The string breaks, and the stone flies off horizontally and strikes the ground after travelling a horizontal distance of 10 m. What is the magnitude of the centripetal acceleration of the stone while in circular motion?

Answer 1

$t=\sqrt{\frac{2h}{g}}=\sqrt{\frac{2\times 2}{9.8}}=0.64s$
$v=\frac{10}{t}=15.68m/s$
$a=\frac{v^2}{R}=168m/s^2$