Question

question 4 of 10
you drop your backpack out of a window from a height of 8.3 m. what is the impact speed of your backpack?
a. 163 m/s
b. 1.2 m/s
c. 12.8 m/s
d. 21.3 m/s

Explanation:

Step1: Identify the relevant formula

We use the kinematic - equation $v^{2}=v_{0}^{2}+2gh$. Since the backpack is dropped, $v_{0} = 0\ m/s$, $g = 9.8\ m/s^{2}$ and $h = 8.3\ m$.

Step2: Substitute the values into the formula

$v^{2}=0 + 2\times9.8\times8.3$.
First, calculate $2\times9.8\times8.3=2\times81.34 = 162.68$. So, $v^{2}=162.68$.

Step3: Solve for $v$

$v=\sqrt{162.68}\approx12.8\ m/s$.

Answer:

C. 12.8 m/s