?: A rocket is fired up at 5 m/s^2. After a certain time, the engine fails and the rocket goes into freefall. It hits the ground 12 seconds after engine failing. Find V(final) and height that the rocket reaches. the the way down... Vf = Vi - at set Vf = 0 b/c when it hits the ground, V = 0 Vi = 9.8(12) Vi = 117.6 m/s so plugging this back into the trip up... Vf = Vi - at Vf = 117.6 m/s Vi = 0 b/c it starts at 0 before fired. 117.6 m/s = - (5 m/s^2)t t = 23.52 sec i hope this is right so far... so how do i find V(final) and the height using this? the rocket doesn't stop when the engine dies. it continues up for a little bit before starting the freefall... thx guys.