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A pelican dives downward from a height of 35 m with an acceleration of 9.8 m/s² to grab a sardine at the surface of the ocean. How long does the dive take?

OA) 0.75 s
OB) 1.9 s
OC) 2.7 s
OD 7.1 s​

User Dundo
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1 Answer

4 votes

Answer:

The dive takes 2.673 seconds.

so OC i think

D = ViT + 1/2 at^2 If the pelican is traveling at 0 m/s vertically at t=0 then that means Vi=0Additionally, if you consider the fact that the distance traveled and acceleration is both the same direction, then sign doesn't matter: 35 = (0) x t + 1/2 (9.8) t^2

35 = 4.9t^2

7.14286 = t^2

t = 2.673s

and you round up to the whole number which would leave your answer to be > OC: 2.7s

User Predrag Samardzic
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