Answer to Question #163630 in Mechanics | Relativity for Hej

Question

A stationary ball drops from the bleachers and reaches the ground at 11m/s. What is the height of the bleachers? Round to the nearest whole number

Answer 1

By energy conservation law:

$mgh=mv^2/2$

$h=\frac{v^2}{2g}=\frac{11^2}{2\cdot9.8}=6m$