Ball falling. In view for .16 seconds. From what height did it fall?

AI Thread Summary
A ball falls from a building and is visible for 0.16 seconds while passing a 1.7-meter-long window. The equations of motion are applied, specifically using h = 1/2 * g * t^2 for the distance fallen and h + 1.7 = 1/2 * g * (t + 0.16)^2 for the total distance. The calculations suggest that the initial approach yields an incorrect height of 0.125 meters. It is concluded that while the exact height of the building cannot be determined with the given data, the distance from the roof to the window can be calculated. The problem emphasizes the need to solve the two equations simultaneously to find the relationship between the height and time.
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Homework Statement



A ball falls from the top of a building.
It falls past a window. It is in view for .16 seconds.
The window is 1.7 m long.
How high was the building off which it was dropped?

Homework Equations


I'm trying to use
.5 a t^2 + vt + x
but it's not working


The Attempt at a Solution


using that, I got .125, which doesn't make sense.
 
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If the ball takes t s to cross the top of the window, it takes (t + 0.16) s to cross the bottom of the window. If h is the distance of the window from the top of the building, then

h = 1/2*g*t^2 ...(1)

h + 1.7 = 1/2*g*(t + 0.16)^2...(2)

Solve the two equations to find h and t.
 
You really can't tell how tall the building is with the information given. You can, however, tell how far the roof is above the window.
 
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