Question

23jan acceleration (20pts)
johnny climbed up to the top of a tree. however, johnny fell out of the tree with an acceleration of 9.8m/s². how long will it take johnny to hit the ground if he reaches the ground at a speed of 58m/s? remember, johnny weight is 160lbs.
place the number in the first box (do include the negative symbol if needed and use three decimal places) and the units in the second box

Explanation:

Step1: Recall acceleration formula

Acceleration $a = \frac{v - u}{t}$, rearrange to $t=\frac{v - u}{a}$

Step2: Define known values

Initial velocity $u=0\ \text{m/s}$, final velocity $v=58\ \text{m/s}$, $a=9.8\ \text{m/s}^2$

Step3: Substitute values into formula

$t=\frac{58 - 0}{9.8}$

Step4: Calculate time value

$t=\frac{58}{9.8} \approx 5.918$

Answer:

5.918
seconds