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

AI Thread Summary
The discussion revolves around a rocket's upward acceleration of 4m/s² while overcoming gravity, which is 10m/s². To achieve this net acceleration, the rocket's engines must produce an upward force that results in a total acceleration of 14m/s². There is confusion regarding the book's claim that the acceleration caused by the fuel is only 4m/s². The correct understanding is that the rocket's engines must provide sufficient thrust to exceed gravitational pull, leading to the conclusion that the net upward acceleration is indeed 4m/s² after accounting for gravity. This highlights the importance of distinguishing between net acceleration and the total thrust provided by the rocket's engines.
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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?
 
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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
 
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