Question 118276
A ball is thrown directly upward from ground level with an initial speed of 80 ft/s. How high will it go and when will it return to the ground?
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EQUATION:
h(t) = -16t^2+vot+so
Your Problem:
so=0 because it is thrown upward from the ground.
You want h(t) to be 0 because you want to know when it hits the ground.
-16t^2+80t=0
-16t(t-5)=0
t=0 or t=5
This means the ball was on the ground when time was zero and it
will be on the ground again when time is 5 seconds.
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Cheers,
Stan H.