Chapter 2, Problem 8MCQ

A ball is thrown downward at a speed of 20 m/s. Choosing the +y axis pointing up and neglecting air resistance, which equation(s), which equation(s) could be used to solve for other variables? The acceleration due to gravity is g =9.8 m/s² downward.

1. $\text{v}=\left(\text{2}0\text{ m}/\text{s}\right)-\text{gt}.$

$\text{y}={\text{y}}_{\text{0}}\left(-\text{2}0\text{ m}/\right)\text{t}-\left(\text{1}/\text{2}\right){\text{gf}}^{\text{2}}$

${\text{v}}^{\text{2}}={\left(\text{2}0\text{ m}/\text{s}\right)}^{\text{2}}-\text{2g}\left(\text{y}-{\text{y}}_{\text{0}}\right)$ .

$\left(\text{2}0\text{ m}/\text{s}\right)=\left(\text{v}+{\text{v}}_{\text{0}}\right)/\text{2}$

All of the above