But the concepts and definitions have not changed?
They have evolved. Read "The Structure of Scientific Revolutions", by Thomas Kuhn.
Newtonian Physics didn't suddenly become invalid just because of General Relativity.
Newtonian physics talks about macroscopic laws; whereas, "General Relativity" is still a theory?
Newtonian Physics is also a theory.
I think it has been proved.
Actually the Webb Space Telescope shows one of those proofs extremely clearly - visually obvious gravitational lensing of distant objects.
Also GPS location would fail without GR corrections.
Then why have we been taught that there are three LAWS of Motion due to Newton?
The gravity of Earth , denoted by g , is the net acceleration that is imparted to objects due to the combined effect of gravitation (from mass distribution within Earth) and the centrifugal force(from the Earth's rotation).
Gravitational acceleration contributes to the total gravity acceleration, but other factors, such as the rotation of Earth, also contribute, and, therefore, affect the weight of the object. Gravity does not normally include the gravitational pull of the Moon and Sun, which are accounted for in terms of tidal effects.
Until someone BREAKS those LAWS, we won't need any physics police.
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Are we actually 100% clear on that point?
I think this is turning into a discussion for the bar sub-category...
let's stop hijakcing OP's thread
I agree, although it seems to be filling a vacuum at the moment.
A good place to start is to understand the relationships of physics to gravity:
Gravity Concepts and Applications (gsu.edu)
You can then pick an area where the gravitational measurement is calculated by forces you can measure at home.
From your figure, it is clear that Gravity is a Force; whereas, "acceleration of gravity" is not a Force. The tile of OP's thread clearly asks for the "Measurement of Gravity".
Where in my response did I use the term "acceleration?"
Clearly you mixed "me" up with some other member.
Added:
How to Calculate Force of Gravity: 10 Steps (with Pictures) (wikihow.com)
To elaborate on my analogy, length is a dimension, whereas a ruler is not a dimension. Nevertheless, you can use a ruler to measure a dimension.
Acceleration is related to Force by F=MA. If M is known, you can obtain F if you measure A.
The word "acceleration" is in the figure of your post #33 -- "Acceleration of Gravity".
That is because gravity is a form of acceleration. If you want to make it more "down to earth" (excuse the words), you could say, "acceleration due to the force of gravity".
A meaningful discussion depends on what the OP is trying to understand or accomplish.
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I am a newbie. Was wondering if I could use the following device:
