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September 21, 2014

September 21, 2014

Posted by **Millie** on Sunday, October 2, 2011 at 5:23pm.

- physics -
**bobpursley**, Sunday, October 2, 2011 at 5:33pmtime is the same.

first stone

hf=hi+vi*t-1/2 g t^2

figure the height of reach floor, and simplify the equation in this form

0=hi+vi*t-1/2 g t^2

second stone

or -hi=vi*t-1/2 g t^2

second stone> do the same thing, you should get

- hi*1/3=V*t-1/2 g t^2

or -hi=3V*t-3/2 g t^2

set the first and second equation equal

and do some algebra to get

t(3V-vi)=1/2 gt^2(3-1) and check that (I did it in my head).

YOu know t, vi, g, solve for V

check my head algebra.

- physics -
**Millie**, Sunday, October 2, 2011 at 7:59pmI'm really confused by this. What am i supposed to use for t in the first equation if i only know that t going up is t and t going down is 4-t. I can't find two variables with one equation and the first equation is solving for hf.

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