Quadratic Equation
posted by Mike .
A ball is thrown upwards from a roof top, 80m above the ground. It will reach a maximum vertical height and then fall back to the ground. The height of the ball from the ground at time T is H, which is given by
H= 16t2 + 64t +80

well, you have the function. Using it, you can find the initial speed (64 ft/s), maximum height (at the vertex), and how long it takes to hit the ground (when h=0).
Incidentally, it is odd that the initial height is given in meters, but the 16t^2 is in ft/s^2. 
I'm assuming that the ht. of bldg. is 80 FT.
instead of 80m.
V = Vo + g*Tr = 0.
64 + 32Tr = 0,
Tr = 2 s. = Rise time or time to reach max height, H.
H = 16*2^2 + 64*2 + 80 = 144 Ft.
0.5g*Tf^2 = 144.
16Tf^2 = 144,
Tf = 3 s. = fall time.
T = Tr + T = 2 + 3 = 5 s. = Time in flight.
Respond to this Question
Similar Questions

Physics
You toss a tennis ball straight upward. At the moment it leaves your hand it is at a height of 1.5 m above the ground, and it is moving at a speed of 8.0 m/s. (a) How much time does it take for the tennis ball to reach its maximum … 
MATH HELP
A soccer ball is kicked toward the goal. The height of the ball is modeled by the function h(t) = −16t2 + 48t where t equals the time in seconds and h(t) represents the height of the ball at time t seconds. What is the axis of … 
algebra
A soccer ball is kicked toward the goal. The height of the ball is modeled by the function h(t) = −16t2 + 48t where t equals the time in seconds and h(t) represents the height of the ball at time t seconds. What is the axis of … 
Maths
A ball is thrown vertically upwards at 3 m s1 from 1m above ground level (I) write down the equation for the height of the ball above the ground after t seconds (while the ball is in the air). (II) use your answer to find the time … 
Maths
A ball is thrown vertically upwards at 3 m s1 from 1m above ground level (I) write down the equation for the height of the ball above the ground after t seconds (while the ball is in the air). (II) use your answer to find the time … 
Applied Calculus
From a height of 25 meters a ball is thrown vertically upwards at a velocity of 5 meters per second. a. What time in seconds will the ball reach its maximum height? 
Quadratic equations
A ball is thrown vertically upwards From the top of a building of height 29.4 m and with an initial velocity 24.5 m/sec. If the height H of the ball from the ground level is given by H = 29.4 + 24.5t  4.9t², then find the time taken … 
Quadratic equations
A ball is thrown vertically upwards From the top of a building of height 29.4 m and with an initial velocity 24.5 m/sec. If the height H of the ball from the ground level is given by H = 29.4 + 24.5t  4.9t², then find the time taken … 
Quadratic Equation  Henry
Hoping Henry can help on previous prob. A ball is thrown upwards from a roof top, 80ft above the ground. It will reach a maximum vertical height and then fall back to the ground. The height of the ball from the ground at time T is … 
Math
Hoping Henry can help on previous prob. A ball is thrown upwards from a roof top, 80ft above the ground. It will reach a maximum vertical height and then fall back to the ground. The height of the ball from the ground at time T is …