SOLUTION: A frog jumps straight up off the ground with an initial vertical velocity of 2 feet per second. After how many seconds does the frog land on the ground? Use the vertical motion mod

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Question 892229: A frog jumps straight up off the ground with an initial vertical velocity of 2 feet per second. After how many seconds does the frog land on the ground? Use the vertical motion model. h=-16t^2 + vt + s
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
h=-16t%5E2+%2B+vt+%2B+s with
t=time in seconds,
h= height in feet above the ground,
s= initial height in feet above the ground (at time zero), and
v= initial velocityin feet per second,
In this case v=2 and s=0 , so
h=-16t%5E2+%2B+2t+%2B+0 or simply h=-16t%5E2+%2B+2t
Factoring, we get
h=%28-16t+%2B+2%29%2At
When the frog is on the ground, h=0 , and
0=%28-16t+%2B+2%29%2At has 2 solutions: system%28t=0%2C%22or%22%2C-16t%2B2=0%29
t=0 is the time when the frog pushed off the gound.
The solution to -16t%2B2=0 gives us the time the frog is on the ground again.
-16t%2B2=0-->2=16t-->2%2F16=t-->highlight%28t=1%2F8%29 or highlight%28t=0.125%29
The frog lands after 1%2F8 of a second (or 0.125 seconds).