Question

question 12 of 25
an apple falls out of a tree from a height of 2.3 m. what is the impact speed of the apple?
a. 6.71 m/s
b. 3.12 m/s
c. 9.11 m/s
d. 45.1 m/s

Explanation:

Step1: Identify the relevant kinematic - equation

The kinematic equation $v^{2}=v_{0}^{2}+2a\Delta y$ is used. The initial velocity $v_{0} = 0$ m/s (starts from rest), the acceleration $a = g=9.8$ m/s² (acceleration due to gravity near the Earth's surface), and $\Delta y=2.3$ m.

Step2: Substitute the values into the equation

Since $v_{0} = 0$ m/s, the equation simplifies to $v^{2}=2g\Delta y$. Substituting $g = 9.8$ m/s² and $\Delta y = 2.3$ m, we get $v^{2}=2\times9.8\times2.3$.
$v^{2}=45.08$.

Step3: Solve for $v$

Take the square - root of both sides: $v=\sqrt{45.08}\approx6.71$ m/s.

Answer:

A. 6.71 m/s