Physics
posted by RePost on .
"You throw a rock at 25m/s at an angle of 25.8511 degrees hitting a target 50m away on the ground in 2.22s." (this is on a flat surface)
Vi=25m/s
Theta=25.8511 degrees
x=50m
t=2.22s
and of course g=9.81m/(s^2)
"How high does the rock fly in the air?"
I know this problem should be a simple plug and solve but my answer does not match the one in the back of my book which is 6.05m. Test coming up and I want to know how to reach that answer or if the book is wrong, what the right answer is.
Please show steps and what equation to use.

my calculator is definitely in degrees

Vi = 25 sin 25.8 = 10.9 m/s up
v = Vi  9.8 t
how long till v = 0?
9.8 t = 10.9
t = 1.11 seconds
how high?
h = ho + 10.9 (1.11)  4.9 (1.11)^2
= ho + 12.1  6.04
= ho + 6.06
ho is because you rally did not throw the rock from ground level did you?
I did not bother to carry 3 sig figs, you may do so of course