I am totally unable to understand kepler's third law of planetary motion
Kindly refer to the link given below to get your answer :
https://www.meritnation.com/ask-answer/question/state-and-prove-kepler-s-third-law-of-planetary-motion-by-a/gravitation/3476167
https://www.meritnation.com/ask-answer/question/state-and-prove-kepler-s-third-law-of-planetary-motion-by-a/gravitation/3476167