Acceleration Part 3: Is Constant Ga Assumption Valid?

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The discussion centers on the validity of the assumption of constant gravitational acceleration (ga) in the context of motion equations. The equation s=ut+1/2 at² is confirmed to be valid when air resistance is neglected, particularly in space where no external forces act. The assumption holds true in scenarios with constant acceleration, as is the case in a vacuum. Participants suggest that future discussions should remain within the same thread for clarity. The conversation emphasizes the importance of recognizing conditions under which the equations apply.
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Homework Statement



Reconsider the assumption made in part 1 regarding the constancy of ga. Briefly comment on the validity of this assumption.


Homework Equations



part 1-

https://www.physicsforums.com/showthread.php?t=161723

The Attempt at a Solution



The equation used is

s=ut+1/2 at2.

This equation is valid when neglecting air resistance. And is valid as there is no air resistance in space.


(is this correct)
 
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More generally; the equation is valid for constant acceleration (i.e. there exist no external forces) which is the case in space.

(In future, it may be better to contine each question in the same thread!)
 

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