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15. You want to calculate the displacement of an object thrown over a bridge. Using -10 m/s2 for acceleration due to gravity, what would be the total displacement of the object if it took 8 seconds before hitting the water?

User CreekGeek
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1 Answer

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Displacement is d


Vf² = Vi² + 2 g d


(-20²) = (+10²) + 2 (-9.8) d


-19.6 d = 300


d = -15.3 m


negative means lower


time is t


d = Vi t + 1/2 g t²



-15.3 = 10 t + (-4.9) t²



4.9 t² - 10 t -15.3 = 0


t = 3.06 s

Hope this helps -John

User Thmsn
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