Physics
posted by Jay Kay .
A rock is thrown from on a cliff with the velocity of 15 m/s at an angle of 30 degrees. it takes the rock 6.30 seconds to hit the ground. how high was the cliff?

hfinal=hinitial+Vi*t4.9t^2
you have hfinal=0, t, Vi=15sin30, solve for hinitial 
Where does the 4.9 come from though?

1/2 g= 4.9

Oh, is it .5 multiplied by the acceleration of gravity?

yes.

Alright. Thank you so much for your help!
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