Can you combine two accelerations together?

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In the discussion about combining accelerations, the user initially miscalculated the maximum altitude of a rocket by subtracting gravitational acceleration from the rocket's vertical acceleration. The correct approach is to use the rocket's acceleration as is, since it represents the actual acceleration provided by the rocket's thrust. Gravity is typically accounted for in the context of projectile motion, but in this case, the given acceleration already includes the effects of gravity. Therefore, combining the two accelerations through subtraction is incorrect. Understanding how to properly interpret the provided acceleration is crucial for accurate calculations in physics.
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When I was doing an exercise on projectile motion, there was a question that asked something like the max. altitude reached by an accelerating rocket. After some calculations, I got 23.96ms-2 as the vertical acceleration, then I minus it with 9.8ms-2 (gravitational acceleration as the two accelerations, I thought, should work against each other). Turns out, this is wrong and I should calculate the rest with 23.96ms-2 as the vertical acceleration. So my question is, why am I not supposed to minus 23.96 with 9.8? Because you can combine tangential acceleration and radial acceleration together to give a "resultant acceleration", but why is it not my case?

Thanks!
 
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I think you'll have to post the original question to get a clear reply. All that comes to mind is that gravity had already, in some way, been accounted for.
 
Question 65
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As Puma suggested, the acceleration given in the problem is the actual acceleration of the rocket, not the thrust of the engine.
 
Thank you guys!
 
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