Question

A ball dropped from rest falls freely until it hits the ground with a speed pf 20 m/s. The time during with the ball is in free fall is approximately

Answer 1

Answer:

$\large \boxed{\text{2.0 s}}$

Explanation:

$\begin{array}{rcl}v & = & gt\\\text{20 m \cdot s}^{-1} & = & \text{9.807 m \cdot s}^{-2} \times t\\t & = & \dfrac{20}{9.807 \text{ s}^{-1}}\\\\& = & \textbf{2.0 s}\\\end{array}\\\text{The ball is in free fall for \large \boxed{\textbf{2.0 s}} }$