### Why Free Fall has no dependancy on mass, but gravity, yes?

Posted:

**Mon Mar 13, 2017 1:31 pm**Hi All,

Since monthes, I (re-)discovered an old difficulty. This one substantialised itself to the more recent days.

Here it is:

Galileo Galilei showed that objects in free fall (further in the text: "fall") had no dependancy on the mass.

And then, a guy named Newton, came, and we understood:

"G M*m/r^2", where:

G is gravific constant,

M is the mass of the planet (Earth),

m is the mass of the object,

and r: the distance over the ground, ("^2" meaning: value at the square).

-I just bought the Newton's Principia, (translated from latin to english), and I made searches: "Universal gravity": 0 result;

"Universal": about 50 results, (Newton worship to use the term Universal, Before making a theoretical assumption, what is contradictory);

"gravity": about 25 results.

-I know that we rendered Newton compatible with Galileo: With the inertial mass, which compensate the attractive mass.

-During the searches, no way, no place to see the equation in such. Actually, you'll find several paragraphes, where the famous equation may be extracted, but depending on 1 sole interpretation.

Reading him, I can find paragraph(s), which may lead to this equation; but understanding him naturally, I cannot extract this equation with certitude, (i. e.: rather than another).

Could someone help me, in finding the most accurate paragraph leading to the famous equation?

-In particular, I'd like to know how (or if) Newton auto-justified himself about the ability to see 2 instantly, for ever, opposed phenomenonS: Inertia and Attractivity ?

Since monthes, I (re-)discovered an old difficulty. This one substantialised itself to the more recent days.

Here it is:

Galileo Galilei showed that objects in free fall (further in the text: "fall") had no dependancy on the mass.

And then, a guy named Newton, came, and we understood:

"G M*m/r^2", where:

G is gravific constant,

M is the mass of the planet (Earth),

m is the mass of the object,

and r: the distance over the ground, ("^2" meaning: value at the square).

-I just bought the Newton's Principia, (translated from latin to english), and I made searches: "Universal gravity": 0 result;

"Universal": about 50 results, (Newton worship to use the term Universal, Before making a theoretical assumption, what is contradictory);

"gravity": about 25 results.

-I know that we rendered Newton compatible with Galileo: With the inertial mass, which compensate the attractive mass.

-During the searches, no way, no place to see the equation in such. Actually, you'll find several paragraphes, where the famous equation may be extracted, but depending on 1 sole interpretation.

Reading him, I can find paragraph(s), which may lead to this equation; but understanding him naturally, I cannot extract this equation with certitude, (i. e.: rather than another).

Could someone help me, in finding the most accurate paragraph leading to the famous equation?

-In particular, I'd like to know how (or if) Newton auto-justified himself about the ability to see 2 instantly, for ever, opposed phenomenonS: Inertia and Attractivity ?