Universal law of gravitation

No. We can't even explain it today. But Einstein expanded the discussion to include not ony mass but energy and pressure...via the Einstein tensor.....somehow all are related at some fundamental level....

 

This doesn't prove how or why they are attracted this is only used to find the force due to gravity between the two objects.

 

The Law of Universal Gravitation is just that: a law. It is a mathematical relationship derived from empirical observation.

 

Is this a homework question? This direcly pertains to an oft quoted passage in Principia: "hypotheses non fingo..."; I make no hypothesis...

 

To my knowledge he did show that from his law of gravitation (and some assumptions) you can derive Kepler's laws of planetary motion, which up to that point were more or less unexplained. I'm no historian, but according to Bate [1], Newton didn't originally publish his results due to a small inconsistency when he applied his theory to calculate the position of the moon and only by chance 20 years later through conversations with Halley did he get around to start working on Principia.


[1] Fundamentals of Astrodynamics, Bate, Mueller, White. Dover, 1971.