Zuchongzhiyuanzhou rate
He carefully studied the work of Liu Xin, Zhang Heng, Zheng Xuan, Kan Yi, Wang Fan, Liu Hui and other scientists, and refuted them one by one. errors and derived many valuable results. The cycle rate value accurate to 7 significant mathematical digits is a well-known example.
Mo Zhai Mathematics, mechanics, acoustics, optics
1. In terms of mechanics, Mohists gave a scientific definition to "force". The study of lever balance takes into account not only the size of the force, but also the length of the moment arm, and actually puts forward the concept of torque. It can be said that the Mohists have discovered the equilibrium condition of leverage.
In addition, Mohists have profound discussions on issues such as motion and time, axles, inclined planes, ball motion, and buoyancy.
In terms of acoustics, the Mohist's outstanding achievement is the ingenious use of solid sound transmission and sound resonance in military affairs.
2. In terms of optics, Mohists studied more. They conducted the world's earliest small hole imaging experiment. In addition, Mohists also did a lot of research on the shadow of flying birds, the umbra and penumbra of objects, the imaging phenomena of concave mirrors and convex mirrors, etc.
Zhang Heng’s Celestial Movement and Cosmic Structure Armillary Sphere Hou Fengyi
Based on his own understanding of the movement patterns of celestial bodies and actual observations, he carefully studied these three theories and believed that the Armillary Sphere theory is more consistent with observations. actual. He inherited and developed the Huntian theory of his predecessors and boldly put forward many new insights into celestial phenomena.
Based on the armillary sphere invented by Geng Shouchang of the Western Han Dynasty, Zhang Heng created an "armillary sphere" that was much more accurate and comprehensive than before based on his own theory of armillary sky. Created an "armillary sphere" that can accurately express the thoughts of armillary sky.
He also created an instrument for measuring wind direction - Hou Fengyi, also called the Xiangfeng Bronze Bird. A bronze bird with a flower in its mouth is placed on the top of a five-foot-high pole, which can rotate with the direction of the wind. The direction the bird's head faces is the direction of the wind.
Shen Kuo's "Mengxi Bi Tan"
A very knowledgeable and accomplished scientist, one of the most outstanding scientists in the history of our country. Proficient in astronomy, mathematics, physics, chemistry, geology, meteorology, geography, agriculture and medicine; he is also an outstanding engineer and an outstanding diplomat.
. The insights and achievements recorded in "Mengxi Bi Tan" cover various fields such as mechanics, optics, magnetism, and acoustics. In particular, he made outstanding achievements in the study of magnetism. Shen Kuo explicitly talked about the declination of the magnetic needle for the first time in "Mengxi Bi Tan". In terms of optics, Shen Kuo made popular and vivid discussions on pinhole imaging, concave mirror imaging, and the magnification and reduction effects of concave and convex mirrors through personal observation and experiments. He also made some scientific explanations for the reasons for the light transmission of the so-called "light-transmitting mirror" (a bronze mirror with front patterns on the back that can be seen on the back) passed down from ancient my country, which promoted the later development of the "light-transmitting mirror". research. In addition, Shen Kuo also experimented with paper-cutting figures on the piano to study the acoustic vibration phenomenon. Shen Kuo was the first to discover that the geographical north and south poles do not coincide with the N and S poles of the geomagnetic field, so there is a small declination between the horizontally placed small magnetic needle and the geographical north-south direction. is called magnetic declination.
Luban Machinery, Civil Engineering, Handicrafts
While climbing a mountain, his finger was scratched by a piece of grass. He picked the grass and looked carefully, and found that the grass blades were all arranged on both sides. With uniform small teeth, he imitated grass blades to make a saw for felling wood. When he saw various birds flying freely in the sky, he cut a flying harrier out of bamboo wood and tried to fly in the air with the help of wind. He started flying for a short time, but after repeated research and continuous improvement, he was able to fly in the air for a long time. Gongshu Ban focused on practice throughout his life, was good at using his brain, and made great contributions in construction, machinery, etc. He was able to build "palaces, terraces and pavilions"; he made "cloud ladders" for sieges and "gouqiang" for boat warfare; he created wooden carriages with "organ preparations"; he invented the ruler, ink fountain, plane, chisel, etc. Various woodworking tools, grinding, grinding, locking, etc. were also invented. Due to his outstanding achievements, construction craftsmen have always respected him as the "ancestor". Luban has many inventions and creations. Many ancient books record that many woodworking tools used by carpenters were invented by him. Like the curved ruler used by carpenters, it is called Luban ruler. Another example is the ink fountain, umbrella, saw, plane, drill, etc. It is said that Lu Ban invented it. It all contains original physical science knowledge.
Lu Ban is also a very clever mechanical inventor. The lock he made has a mechanism on the inside, leaving no trace on the outside. It can only be opened with the help of a well-matched key.
There is a record in the book "Mozi": "Gong Shuzi whittled bamboo wood to make a magpie, and when it was completed, it flew and did not fly for three days." That is to say, the wooden bird made by Lu Ban could fly with the power of the wind. Go high in the sky and don't land for three days. Can this be considered the pioneer of primitive aviation science?
Luban also improved the structure of vehicles and made mobile wooden carriages and horses. This kind of wooden chariot and horse is controlled by a wooden man, equipped with mechanisms, and can walk automatically.