Problema Solution
A rocket is launched from a top of a 101 foot cliff with an initial velocity of 116 ft./s.
a) use the quadratic formula to find out how long the rock it will take to hit the ground after it is launch. Round to the nearest second.
Answer provided by our tutors
Assuming the quadratic formula is:
h=-16t^2+vt+c, where h is the height, v = 116 ft/s, c = 101 ft
We need to find t, t>0, such that h = 0, that is:
-16t^2+116t+101 = 0
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click here to see the equation solved for t
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t = 8 s
We need to ignore the negative solution since the time cannot be negative.
It will take 8 seconds for the rock to hit the ground.