A rocket is fired vertically and ascends with a constant vertical acceleration of 20 m/s^2 for 1 minute. It's fuel is then all used and it continues as a free particle. Find the
Maximum height reached by the particle
Total time elapsed from the take off till the rocket strikes the earth.
I cannot understand this question practically. First of all does the acceleration include $g$ in it . Also is it deacceleration or acceleration in this case. If it is acceleration then how can the velocity become zero in 60 sec. Also is the initial velocity zero ? I feel that there should be an initial velocity like in the case of projectile motion. Please guide me in this question.