Question

A stone was dropped off a cliff and hit the ground with a speed of 88 ft/s . What is the height of the cliff? (Use 32 ft/s 2 for the acceleration due to gravity.)

Answer 1

To solve this problem we will apply the linear motion kinematic equations, which describe the change in velocity, depending on the acceleration and the distance traveled, that is,

`v_f^2 = v_i^2 +2ah`

Where,

`v_f`= Final Velocity

`v_i` = Initial Velocity

a = Acceleration

h = height

Our values are given as,

`v_f = 88 ft/s\\v_i = 0 ft /s\\a = 32 ft/s^2\\`

Replacing we have,

`vf^2 = vi^2 + 2*a*h`

`88^2 = 0 + 2*32*h`

`h= 121 ft`

Therefore the height of the cliff is 121ft