Solving the Falling Man Problem: Calculating Building Height

alafleur1
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How would i go about solving this?

A man falls off a building with height D. He travels 1/4D in the last 1 second of fall. How high is the building?
 
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well y = y_0-v_0*t-1/2 g*t^2

you have 1/4 delta y in 1sec

do you see how to continue
 
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