How Do I Calculate the Height of a Fence in Projectile Motion?

AI Thread Summary
To calculate the height of the fence in the projectile motion problem, first determine the maximum height of the golf ball, which occurs 8.3 seconds after being hit. After reaching this height, the ball falls for an additional 1.2 seconds before clearing the fence located 482 feet away. The vertical distance fallen during this time can be calculated using kinematic equations, assuming an initial vertical velocity of 0. Subtract the distance fallen from the maximum height to find the height of the fence. This approach effectively utilizes the principles of projectile motion to solve the problem.
physics=headache
ok i am so lost as to how to start this problem. the problem goes like this :
assume g = 32ft/s^2
A golf ball is hit at ground level. the ball is observed to reach its maximum height above ground level 8.3 s after being hit. 1.2 s after reaching this maximum height, the ball is observed to barely clear a fence that is 482 ft from where it was hit. How high is the fence? answer in units of ft.

i think the problem I'm having with this problem is figuring out the height of the fence, i know how to figure out the max height, but where do i go from that. i know all the formulas for kinematics in 2 dimensions. i would appreciate any help u can give me.

thanks
 
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482 feet is there just to confuse you (or to give you some information about the horizontal speed of the ball, in case there are more parts to the problem).

As far as the height of the fence is concerned, if you have figured out the maximum height of the ball, just figure out how far the ball falls in 1.2 seconds with initial velocity of 0 (vertical) and subtract that distance from the max. height.
 
thanks for the help

thanks that helped alot
 
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