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coneheadceo
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Homework Statement
A projectile is fired from a cliff 125m off the ground at 37° from the horizontal at 65 m/s. How long will it take to hit the ground?
Homework Equations
y= yo+(Vyo)(t) - 1/2(g)(t^2)
quadratic formula
The Attempt at a Solution
substituting in equation...
(-125m)= 0 + (65m/s)(t) - 1/2 (9.8 m/s^2)(t^2)
(4.9 m/s^2)(t^2)- 65 m/s (t) -125m =0
rewrite in quadratic to solve for t
t=((65 m/s) +/- √((65)^2-4(4.9 m/s^2)(125)))/ 2(4.9m.s^2)
t = 10.9 s
answer in back of book is 10.4 s
not sure if using proper equation or totally missing something.