An apple falls from a tree and hits the ground 5 m below. It hits the ground with a speed of about
A)5 m/s.
B)10 m/s.
C)15 m/s.
D)20 m/s.
E)not enough information given to estimate

Question

Quizplus · Accepted Answer

Using the formula $v = \sqrt{2gh}$ where $g = 9.8 \, \text{m/s}^2$ (acceleration due to gravity) and $h = 5 \, \text{m}$ (height), we can estimate the speed as $v \approx \sqrt{2 \times 9.8 \times 5} \approx 9.9 \, \text{m/s}$, which is closest to 10 m/s.

An Apple Falls from a Tree and Hits the Ground