Question

while jeff was replacing the obstruction of light on a cell tower, he accidentally dropped his cell phone. If he was 150 ft up at the time, approximately how long did it take the phone to reach the ground

Answer 1

3.19 seconds

Explanation:

Given:

Phone gets dropped from a Height = 150 ft

To find:

Time taken for the phone to reach the ground = ?

Solution:

First of all, let us learn about the formula of distance in terms of Initial speed u; Time t and Acceleration a:

`s=ut+(1)/(2)at^2`

Here the phone is dropped from a height so a = g m/
`s^2` i.e. acceleration due to gravity.

g = 9.8 m/
`s^2`

s = 150 ft

Initial velocity, u = 0

Putting all the values in the formula:

`150=0 t+(1)/(2)gt^2\\\Rightarrow 50=(1)/(2)* 9.8 * t^2\\\Rightarrow t^2=(50)/(4.9 )\\\Rightarrow t^2=10.20\\\Rightarrow t = 3.19\ sec`

So, the time taken is 3.19 seconds.