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I just joined and I have a question. Here is my problem:

Sitting in a second-story apartment, a physicist notices a ball moving straight upward just outside her window. The ball is visible 0.291 s as it moves a distance of 1.22 m from the bottom to the top of the window. What is the greatest height of the ball above the top of the window?

How long does it take before the ball reappears?

This is what I have done so far & I have worked on this problem for days and I am ready to cry, seriously.

I figured out the average velocity as 4.19 m/s.

Then I figured out the velocity at the bottom of the window as 7.05 m/s. After that I try to use the formula to find the position as a function of time with the formula x= x_o + v_0t - .5gt^2. At this point I don't know what to do. Do I put in 0 for x_0 or do I put in 1.22? If I put in 0 and use 0.291 as the time I end up with x = 1.64 m. THat answer isnt right according to LON CAPA. ANd after I do figure out the position how do i figure out the time. Do I just divide the position by the 7.05? I need some major help. I need to know how to set up the last formula. Maybe I need to add my answer to the 1.22 or subtract it. I really don't know. Let me know if anyone can help me. Thank you.

You can also send me an email if you dont want to post on the board.

jackie

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# Homework Help: One-Dimensional Kinematics Problem

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