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1) A ball is dropped from a height of 50 feet. How long after it is dropped will it reach a height of 18 feet?

User Tor Valamo
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1 Answer

6 votes

Answer: 1.41 seconds

Explanation:

The problem gives the initial velocity by saying "dropped." This indicates a velocity of zero. Acceleration can also be found because the object is in free fall. It would experience the acceleration of gravity. We can use the kinematic equation:


(y_f-y_i)=V_it+(1)/(2)at^2

The velocity term completely cancels because the object was dropped with an initial velocity of 0.


(18-50)=(1)/(2) (32.17)t^2\\


-32=-16.085t^2\\t=√(1.989) =1.41s

User Sudarsan GP
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