What is the Newton's version of Kepler's third law?

1 Answer
Jun 26, 2018

Newton's law F_g=G·(M_s·M_p)/R^2 where M_s, M_p are the

mass of Sun and a planet, G is a constant value and R is the distance between Sun and Planet.

Kepler's Law is T^2/R^3=K constant and T is period of traslation in orbit and R again, distance between Sun and Planet.

We know that centrifuge force is given by

F_c=M_p·a=M_p(2pi/T)^2·R where a is acceleration in orbit

Then combining both expresions

T^2/R^3=(4pi^2)/(GM_s)