Brave Fish launching himself in a cannon

[maxtheminawes]

Homework Statement

The brave fish launches himself from a 6 cm cannon straight up in the air. When he leaves the cannon he is traveling at 6.5 m/s. assume constant acc while in the cannon.
How long was the fish in the cannon?

Homework Equations

v^2=Vo^2+2ax
X= Xo + Vot + 1/2at^2
X=height
Xo=initial height
Vo=initial velocity
t=time

The Attempt at a Solution

6.5^2=0^2+2a(.06)
a=352.08m/s^2
352.08=u-9.8 (u=up acc)
u=361.88m/s^2

x=1/2at^2
.06=1/2(361.88)t^2
t=.02sec

 

[PhanthomJay]

Yes, but do not add 'g' to the acceleration. You can get the same result more easily by using $x = [(v_o + v_f)/2]t$.