Solving a Ball & Stone Thrown Vertically Upwards Problem

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A problem involving a ball and a stone thrown vertically upwards requires calculating the height at which they pass each other. The ball is thrown first with an initial speed of 16 m/s, followed by the stone at 21.3 m/s after a delay of 1.1 seconds. The equations of motion are set up correctly, but the mistake lies in the handling of time; the time for the stone should account for the delay. Correcting this will yield the accurate distance where the two objects meet. Proper attention to the timing and equations will resolve the issue.
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Hi..I have a question I guess you guys help me out ...here is the question.

1.A ball is thrown verticaly upward with an initial speed of 16m/s.then 1.1s later a stone is thrown straight up(from the same inital height of the ball ) with inital speed of 21.3m/s.
the acceleration of gravity is 9.8m/s^2.

how far above the realease point will the ball and the stone pass each other?answer in meter.

Here is what i did.
Y(ball) = Y(stone)

V(inital)t + 1/2 9.8t^2 = V(inital)(t -1.1)+ 1/2 9.8t^2

so 1/2 9.8t^2 will cancel out

which left
16m/s t = 21.3t - 23.43

t = 4.4207 second

after that i use the same formula to find distance which is distance of the ball is 166.4898 and distance of stone is 189.9195

finaly i subtacted stone - ball = 23.4297 meter.

but still my answer is incorrect but i don't know where is my mistake ...so i just need little help

thank you
 
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kmikias said:
Hi..I have a question I guess you guys help me out ...here is the question.

1.A ball is thrown verticaly upward with an initial speed of 16m/s.then 1.1s later a stone is thrown straight up(from the same inital height of the ball ) with inital speed of 21.3m/s.
the acceleration of gravity is 9.8m/s^2.

how far above the realease point will the ball and the stone pass each other?answer in meter.

Here is what i did.
Y(ball) = Y(stone)

V(inital)t + 1/2 9.8t^2 = V(inital)(t -1.1)+ 1/2 9.8t^2

Careful with the highlighted time.
 
thank you Kurdt that where i did a mistake.
 
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