Fundamentals of Physics/The Law of Gravity
Gravitation is the name given to the force of attraction between any two bodies in the universe. It was discovered by Sir Issac Newton in the year 1665, when he saw an apple falling down the tree. Gravitational force is the weakest force among the four fundamental forces of nature, but is the most important force because it played an important role in initiating the birth of stars, and controlling the entire structure of the universe.
NEWTONS LAW OF GRAVITATION:- It states that every body in the universe attracts every other bodies with a force which is directly proportional to the product of their masses and is inversely proportional to the square of the distance between them.
Consider two bodies of masses M and m. With distance r apart, and F be the force of attraction between them. Then according to newtons law of gravitation;