Answer:
It slows down from 0-31.25s
It speeds up from 31.25-62.507s
Explanation:
If we find the maximum of the equation, we will know the moment when it changes direction. It will slow down on the first interval, and speed up on the second one.
[tex]Y = -16t^2+1000t+7[/tex]
[tex]Y' = -32t+1000 = 0[/tex] Solving for t:
t = 31.25s
The bullet will slow down in the interval 0-31.25s
Let's now find the moment when it hits ground:
[tex]Y = 0 = -16t^2+1000t+7[/tex] Solving for t:
t1 = -0.0069s t2 = 62.507s
The bullet will speed up in the interval 31.25-62.507s
