Question 1119773
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The ball started with velocity v directed vertically up, and was decelerated with the deceleration of g = 9.81 m/s^2


(the gravity acceleration at the Earth surface).


For the goals of this problem you can accept g = 10 m/s^2.


Then the equation to stop moving up is


    0 = v - gt,   or  v = g*t = 10*3 = 30 m/s.


<U>Answer</U>.  The initial velocity of the ball was  30 m/s.
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