physics
posted by Fefe .
A student drops a ball from the top of a tall building; the ball takes 2.8 s to reach the ground.
1. what was the ball's speed just before hitting the ground?
2. What is the height of the building?
help please?

assuming it drops from rest you know:
vo=0
t=2.8
a=9.8 (gravity assuming down is +)
v=?
use the equation v=vot+at^2
then you want to find height.
x= vot+.5at^2 
i love you sweat heart

Fu
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