SOLUTION: golf ball is hit at ground level. The ball is observed to reach its maximum height above ground level 6.9 s after being hit. 1.1 s after reaching this maximum height, the ball i

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Question 214252: golf ball is hit at ground level. The ball is
observed to reach its maximum height above
ground level 6.9 s after being hit. 1.1 s after
reaching this maximum height, the ball is
observed to barely clear a fence that is 357 ft
from where it was hit.
The acceleration of gravity is 32 ft/s2 .
How high is the fence? Answer in units of
ft.

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
golf ball is hit at ground level. The ball is
observed to reach its maximum height above
ground level 6.9 s after being hit. 1.1 s after
reaching this maximum height, the ball is
observed to barely clear a fence that is 357 ft
from where it was hit.
The acceleration of gravity is 32 ft/s2 .
How high is the fence? Answer in units of
ft.
----------------------
h(t) = -16t^2 + vt (v = initial vertical speed)
v = 32*6.9 = 220.8 ft/sec
h(t) = -16t^2 + 220.8t
t = 6.9 + 1.1 seconds
h(8) = -16*64 + 220.8*8 = -1024 + 1766.4
h = 742.4 feet
That's a tall fence, I suspect a number isn't right. 13.8 seconds is a LONG flight time for a golf ball.
-----------------
The distance to the fence is not relevant.