Introduction to classical mechanics
The basic law of classical mechanics is Newton's law of motion or other mechanical principles related to Newton's law and equivalent. It is the mechanics before the 20th century. There are two basic assumptions: one is that time and space are absolute, length and time The measurement of the interval has nothing to do with the movement of the observer. The transmission of the interaction between the substances arrives instantaneously; the second is that all observable physical quantities can in principle be measured indefinitely and accurately. Since the 20th century, due to the development of physics, the limitations of classical mechanics have been exposed in the fields of microcosm (quantum scale) and high speed (close to the speed of light).