Mechanics

# Law of universal gravitation

Force of attraction between two particles

After working as Tycho Brahe’s assistant, and shortly after his death, Kepler began to carefully analyze all the notes left by his “master”. As he was a supporter of the heliocentric system proposed by Copernicus, Kepler needed a lot of audacity to show his laws and discoveries, now known as Kepler’s laws.

Although Kepler’s laws geometrically described the motions of the planets, something was still missing, namely, more concise explanations of how the planets moved.

In historical facts, we know that Newton, from the fall of an apple on his head, showed that all the movements of planets, comets, satellites, etc., could be explained starting from the following assumption:

The constant of proportionality, also called the gravitational constant, G, must be obtained experimentally and its value in the International System of Units is: