Can you combine two accelerations together?

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Discussion Overview

The discussion revolves around the concept of combining accelerations in the context of projectile motion, specifically regarding the vertical acceleration of an accelerating rocket and gravitational acceleration. Participants explore the reasoning behind whether these accelerations can be combined or should be treated separately.

Discussion Character

  • Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant describes a scenario involving an accelerating rocket and questions the validity of subtracting gravitational acceleration from the rocket's vertical acceleration.
  • Another participant suggests that the original question may provide necessary context to clarify the situation.
  • A third participant notes that the acceleration mentioned in the problem refers to the actual acceleration of the rocket rather than the thrust of the engine.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the correct approach to combining the accelerations, and multiple viewpoints regarding the treatment of gravitational acceleration remain present.

Contextual Notes

There is a lack of clarity regarding the original problem statement, which may influence the interpretation of how to handle the accelerations. Additionally, the discussion does not resolve whether gravitational acceleration should be considered in combination with the rocket's acceleration.

Zynoakib
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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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