Answer:
A.) 24.08 seconds
B.) 825.42 metres
Step-by-step explanation:
function of time is given as
h ( t ) = − 4.9 t 2 + 118 t + 115 .
Where a = -4.9, b = 118, c = 115
Let's assume that the trajectory of the rocket is a perfect parabola.
The time t the rocket will reach its maximum height will be at the symmetry of the parabola.
t = -b/2a
Substitute b and a into the formula
t = -118/-2(4.9)
t = 118/9.8
t = 12.041 seconds
Since NASA launches the rocket at t = 0 seconds, the time it will splash down into the ocean will be 2t.
2t = 2 × 12.041 = 24.08 seconds
Therefore, the rocket splashes down after 24.08 seconds.
B.) At maximum height, time t = 12.041s
Substitute t for 12.041 in the function
h ( t ) = − 4.9 t 2 + 118 t + 115
h(t) = -4.9(12.041)^2 + 118(12.041) + 115
h(t) = -4.9(144.98) + 118(12.041) + 115
h(t) = -710.402 + 1420.82 + 115
h(t) = 825.42 metres
Therefore, the rocket get to the peak at 825.42 metres
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