Posted by Dee on .
A model rocket launches with an initial velocity of 6 m/s, at an angle of 90 degrees (with respect to the horizon). The rocket's engine provides an acceleration of 2.2 m/s2, acting in the same direction as the initial velocity. After 20 seconds, the rocket engine cuts out.
What is the maximum height attained by the rocket?

Physics 
bobpursley,
at twenty seconds,
vf=vi+at=50.4 m/s check that.
h=(vi*20+1/2 a t^2)= 120+1.1*400=560 check that.
now, how much higher did it go, with an initial velocity of 50.4m/s
vf at top=0
vf^2=vi^2+2ad
0=50,4^219.8d solve for d
Now add d to 560m