Newton was alone in the orchard at home. Because he walked and thought, he accidentally bumped into an apple tree in the garden. At this moment, an apple just hit Newton's head. Newton suddenly woke up from the problem and picked up the apple. At this time, he fell into another problem: why did the apple fall to the ground instead of floating in the sky? Finally, Newton put forward a universal law of the simplest phenomenon: gravity.

Extended information Newton's main achievement: 1679, Newton returned to the study of mechanics: gravity and its influence on planetary orbits, Kepler's laws of planetary motion, and discussions with Hooke and Flamsteed on mechanics. He attributed his achievement to the book Motion of Objects in Orbit (1684), which contains a preliminary law of motion formed in principle later.

With the encouragement and support of edmund halley, Mathematical Principles of Natural Philosophy was published on July 5th, 687/kloc-0. In this book, Newton expounded three laws of motion, which were regarded as truth in the next two hundred years.

Newton named the present gravity with Latin "gravity" and defined the law of gravity. In this book, he also proposed the first method to analyze and measure the speed of sound in the air based on Boyle's law.

Because of his achievements in principle, Newton gained international recognition and won a large number of supporters: Newton established a very close relationship with the Swiss mathematician Nicolas Fatio Diu Lei until their friendship broke down in 1693. The end of this friendship made Newton suffer from neurasthenia.

Newton made an in-depth study on the basis of the work of Galileo and others, and summed up three basic laws of motion of objects (Newton's three laws).

References:

Baidu encyclopedia-Newton