Rockets distance travelled

Allowing for a drag correction of 0.9 in the modest velocity and acceleration of the small firework rocket as described above results in a reduction in the distance travelled from 75.9m to 63.4m. 

Now if a rocket with a velocity u accelerates with a uniform acceleration a, for a time t and attains a velocity v, the distance v travelled by the rocket in the time t is given by... 

In space travel and rocket problems, where the (distances from the earth become significant compared with 4000 mi (so the changing value of gravity must be taken into account)... 

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