Answer :
Answer:
t = 9.58 s
Step-by-step explanation:
Given that,
The height from where the cell phone is dropped, h = 450 feet
We need to find the time for the cell phone to reach the ground. Let the time be t. Using second equation of kinematics to find it.
[tex]h=ut+\dfrac{1}{2}at^2[/tex]
u is initial velocity, u = 0
a = g
So,
[tex]h=\dfrac{1}{2}at^2\\\\t=\sqrt{\dfrac{2h}{g}} \\\\t=\sqrt{\dfrac{2\times 450}{9.8}} \\\\t=9.58\ s[/tex]
So, it will take 9.58 seconds to reach the ground.