An arrow is shot straight up in the air with speed of 20m/s. How long is t in the air? How high will the arrow rise?

Answer 1

F = m a
F = -mg
so a = -g = -9.8
v = Vo -9.8t
0 at top = 20 - 9.8 t
t at top = 20/9.8 (same time falling so double that for time in air)
at t = t at top. how high is it?
h = 20 t - (1/2) (9.8) t^2

Answer 2

amm i got an answer of 4.08 for the time in the air I divided 20/9.8=2.04x2=4.08

For the rise I do not multiply by 2 t right? I got answer of 20.4

I am very glad that you were able to help me with this problem