Question

A cherry falls from a tree branch that is 9 feet above the ground.

Answer 1

The cinematic equation is:
 h (t) = (1/2) * a * t ^ 2 + vo * t + h0
 Where,
 a: acceleration
 vo: initial speed
 h0: initial height
 Substituting values:
 h (t) = (1/2) * (- 32) * t ^ 2 + (0) * t + 9
 h (t) = - 16t ^ 2 + 9
 For t = 0.2 we have:
 h (0.2) = - 16 * (0.2) ^ 2 + 9
 h (0.2) = 8.36 feet
 To touch the ground we have:
 -16t ^ 2 + 9 = 0
 16t ^ 2 = 9
 t = root (9/16)
 t = 0.75 s
 Answer:
 The height of the cherry after 0.2 seconds is:
 h (0.2) = 8.36 feet
 the cherry hits the ground at:
 t = 0.75 s