A Study On The Mechanics Knowledge Of Ancient China

The ancient mechanics of China is one of important part of Chinese ancient physics, with its unique knowledge system and cognition method. In order to make a further understanding of them, Chinese ancient scholars’discussions on 4 systematic mechanical problems, which are the stable mechanism of the earth, the measurement of "Gong", the answers to kinematics problems and the knowledge of rotational phenomenons, are analyzed in this dissertation. And, a brief introduction to this dissertation is as follows:Firstly, by analyzing on the discussions and analogies on the stable mechanism of the earth of Chinese ancient scholars, who were under the influence of traditional culture and western astronomy, the dissertation found that those scholars proved the stable mechanism of the earth they supported, by describing the phenomenons that some common goods in life could float in the water or air. And, even the scholars who had accepted the idea of a spherical earth from the end of Ming dynasty to the middle period of Qing dynasty, held on to the traditional interpretation that the earth was supported by the air. Besides, those scholars’argument analogies had the characteristics that, they were for testify their interpretation purpose, were less about doing and more about describing, and the materials of analogies were chosen from the common goods in life.Secondly, by conducting a systematic analysis of the measurement of "Gong" of transport activities and other activities in ancient China, this dissertation found that concerning the selection of the object of measurement and the independent variables, and the processing of the relationships between the independent variables, the measurement of "Gong" of the transport activities in ancient China were congruent with the calculation of work in the physics. In the measurement of "Gong" of the other activities, whether the independent variables could be used to quantitatively express, the number of and the logical relationship between the independent variables needed to be taken into account. And on this basis, conversion, superposition, building the quantitative relation and other methods were used to deal with relation of the independent variables, thus the relation between dependent variables and independent variables could be established.Thirdly, by systematic analysis and comparison of the solutions of traditional mathematics and modern physics of 50 computational problems, which are chosen from 13 ancient Chinese math-books, this dissertation found that the solutions of traditional mathematics were consistent with those of modern physics in the problems of the uniform motion, while these two kinds of solutions were inherently different in some more complex problems of the uniformly accelerated motion and non-uniformly accelerated motion. And it reflected a unique way of physical cognitive style and solving problems. The ancient Chinese cognitive style of phenomenon of object motion was mathematical rather than physical. Therefore, no general physical concept had been raised, no general physical problem had been extracted, no general kinematics theory had been developed. And, they were at the same cognitive level for a long time.Fourthly, based on the analysis of the ancient scholars’qualitative descriptions and quantitative descriptions of the various rotational phenomenons, this dissertation pointed out that, those qualitative descriptions mainly reflected ancient scholars’ simple understanding of the change rules of the linear velocity and angular velocity of rotating objects. And those quantitative descriptions mainly reflected their basic recognition of quantitative comparison of the rotation and translation, and gear trains could be used to change the directions of velocity and the magnitudes of dynamic action.