The story of Newton s discovery of gravity mainly written about the passage .

Did Newton discover gravity because he was hit on the head by an apple? It's not quite what we thought.

Newton observed the phenomenon of falling objects and found that there is a gravitational force, such as an apple falling from a tree without flying away, such as a stone thrown into the air and falling again, such as water flowing from a high place to a low place, and so on.

Because Newton did not stop at simple observations, but applied mathematics, especially calculus, which led to the application of mathematical tools to extrapolate from Kepler's three laws, and thus discovered the famous gravitational force.

The full name of gravitation is "the law of universal gravitation", which is a law of interaction between objects, discovered by Newton in 1687. Any object has a mutual attraction to each other, and the magnitude of this force is directly proportional to the mass of the individual objects and inversely proportional to the square of the distance between them.

If m1 and m2 are used to denote the mass of two objects, and r denotes the distance between them, then the mutual attraction between objects is f=(gm1m2) r, g is called the gravitational constant or simply the gravitational constant, g is measured by Cavendish using a torsion weighing device, and its value is about n·m kg.

Newton's story of discovering gravity dates back to the late 17th century, when Newton was studying the laws of celestial motion. He developed a keen interest in the motions of planetary orbits and believed that there must be some kind of universal regularity behind these movements. Legend has it that Newton was inspired when he saw an apple fall from a tree

The law of gravitation. Newton realized that the apple fell to the ground because of the Earth's gravitational pull on the apple, which is one of the reasons why the Earth moves around the Sun. Newton began to study the nature of gravitation, and in 1687 he published his Principia Mathematica of Natural Philosophy.

In this book, Newton proposed the law of gravitation, which states that the magnitude of gravitational force between any two objects is inversely proportional to the square of their mass and distance. This law provides an important tool for explaining the motion of celestial bodies, allowing humans to gain a deeper understanding of the phenomena in the sky. While Newton's law of universal gravitation seems simple now, it was a major discovery at the time, laying a solid foundation for physics and astronomy.

Newton also invented calculus, which provided another powerful tool for solving mathematical problems. These discoveries have not only played a huge role in promoting the development of astronomy, but also had a profound impact on human scientific understanding and technological progress.