Question

Newton

a. In "Principia", Newton referred to his law of gravitation as "universal", indicating that it could work everywhere. How is the concept of a universal law contrary to Aristotelian cosmology?

b. Why did Newton choose to derive Kepler's laws, as opposed to anyone else's as consequences of his more general laws?

c. Why did Newton describe the Moon as always falling towards, but never reaching, the Earth?

d. What is ”action at a distance”? Why did Newton call the concept ”absurd”?

Answer 1

(a) Newton's Universal law is contrary to Aristotelian Cosmology beacuse in his law Newton described the concept of gravity which is applicable at everywhere in the universe but Aristotle gave the concept of according to the different weights of different bodies in the universe which was not obeyed by everything.

(b) Kepler’s third law shows that there is a precise mathematical relationship between a planet’s distance from the Sun and the amount of time it takes revolve around the Sun. It was this law that inspired Newton, who came up with three laws of his own to explain why the planets move as they do. Thinking on Kepler’s laws, Newton realized that all motion, whether it was the orbit of the Moon around the Earth or an apple falling from a tree, followed the same basic principles.

(c) As Newton came to the conclusion that any two objects in the Universe exert gravitational attraction on each other, with the force having a universal form, he described the moon as always falling towards earth, but never reaching.

(d) Action at a distance is the concept that an object can be moved, changed, or otherwise affected without being physically touched (as in mechanical contact) by another object. That is, it is the nonlocal interaction of objects that are separated in space.

Newton called it absurd because he had the familiar view that a substance cannot act where it is not and considered non-local action to be simply unthinkable.