225k views
0 votes
A stone was dropped off a cliff and hit the ground with a speed of 128(F)/(s). What is the height of the cliff?

User Vincet
by
7.7k points

1 Answer

4 votes

Final answer:

The height of the cliff from which a stone was dropped and hit the ground with a speed of 128 feet per second is calculated using the kinematic equation. It comes out to be approximately 254.4 feet.

Step-by-step explanation:

To find the height of the cliff from which a stone was dropped and hit the ground with a speed of 128 feet per second, we can use the kinematic equation:

v^2 = u^2 + 2gh

Where:
v = final velocity (128 feet per second)
u = initial velocity (0, since the stone was dropped)
g = acceleration due to gravity (32.2 feet per second squared)
h = height of the cliff (the value we are looking for)

Rearranging the equation to solve for h, we get:

h = (v^2 - u^2) / (2g)

Substituting in the known values:

h = (128^2 - 0^2) / (2 * 32.2)

h = 16384 / 64.4

h = 254.4 feet.

Therefore, the height of the cliff is approximately 254.4 feet.

User Brewster
by
7.2k points