A ball is thrown straight up from the edge of the roof of a building. A second ball is dropped from the roof a time of 1.14 later. You may ignore air resistance.(adsbygoogle = window.adsbygoogle || []).push({});

A- If the height of the building is 19.3 , what must the initial speed be of the first ball if both are to hit the ground at the same time?

B- Consider the same situation, but now let the initial speed of the first ball be given and treat the height of the building as an unknown. What must the height of the building be for both balls to reach the ground at the same time for v0 = 8.80 .

i need a help for this question please.. 3 hours and im getting a wrong answers..

i used these formulas : y=v0.t-1/2.g.t2 , and this : y=1/2.(v0-v).t

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# Homework Help: Balls dropped and thrown at the same time

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