What Causes a Rocket's Upward Acceleration of 4m/s² Despite Gravity?

[pivoxa15]

Homework Statement

A rocket projected vertically upwards shows an observed/measured acceleration of 4m/s^2 in its motion.

What is the upwards acceleration of the rocket caused by the fuel?

Homework Equations

gravity = 10m/s^2

The Attempt at a Solution

There is an acceleration of gravity acting on the rocket all the time so for it to show an acceleration of 4m/s^2, the internal engine must be making it to accelerate vertically upwards at 14m/s^2. Am I correct?

 

[Hootenanny]

Yesstupid text limit[/color]

 

[pivoxa15]

I thought so too as one can show using forces that in order to have a net force, the rocket must be providing 14m/s^2 acceleration. But the book claims the answer is 4m/s^2