Question

1. A can is dropped from rest at a height of 40.0 m above ground. How much time does it spend in the bottom half of its fall?

Answer 1

Given:

$h=\rm 40\:\rm m$

$g=9.8\:\rm m/s^2$

The time of free falling

$$t=\sqrt{\frac{2h}{g}}=\sqrt{\frac{2*40}{9.8}}=2.9\:\rm s$$