Calculating height achieved under changing gravitional field

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The discussion revolves around the integration of the gravitational acceleration equation g = GM/r^2 to derive velocity as a function of radius. The initial attempt to use the equation ?Y = VoT + 0.5AT^2 for non-uniform acceleration is deemed inappropriate, as it only applies to uniformly accelerated motion. The correct approach involves integrating the relationship between velocity and radius, leading to the equation v^2/2 = GM/r + C. The participants clarify that the original reasoning is flawed and question the specific problem being addressed, indicating that finding the height of a projectile as a function of time is more complex than initially thought. The conversation emphasizes the importance of using appropriate equations for different types of motion.
relativitydude
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For some reason, this is alluding me at the moment. We know the gravitational acceleration equation is g = GM/r^2, integrate that in respect to r to yield -GM/r

I thought I could use

?Y = VoT + .5AT^2

and subsitute GM(-1/Ro + 1/R) into A

For some reason this is not working, is my line of reasoning correct?
 
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relativitydude said:
We know the gravitational acceleration equation is g = GM/r^2, integrate that in respect to r to yield -GM/r
Not exactly:
g = dv/dt = - GM/r^2
v dv/dr = - GM/r^2
Now you can integrate with respect to r:
v^2/2 = GM/r + C


I thought I could use

?Y = VoT + .5AT^2
That's only good for uniformly accelerated motion.
For some reason this is not working, is my line of reasoning correct?
No. What problem are you trying to solve? The height of a projectile as a function of time? That's not so simple.
 
Thank you very much! :)
 
So I know that electrons are fundamental, there's no 'material' that makes them up, it's like talking about a colour itself rather than a car or a flower. Now protons and neutrons and quarks and whatever other stuff is there fundamentally, I want someone to kind of teach me these, I have a lot of questions that books might not give the answer in the way I understand. Thanks
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