The law of conservation of energy is one of the basic laws of nature, so how did it come into being? The law of conservation of energy comes from the study of the absurd perpetual motion machine, which is really an interesting thing that makes people laugh and cry: the absurd perpetual motion machine is like a mother. After she gave birth to the law of conservation of energy, her son sentenced her to death.
It turns out that in the face of perpetual motion machine, repeated battles and failures force people to pay attention to the study of the nature of energy and the mutual transformation and quantitative relationship of various energies. It's natural. "Perpetual machine" is a "machine" that converts one kind of energy into another and provides energy forever.
The perpetual motion machine fever is colder than 1775 when the Paris Academy of Sciences decided to stop reviewing the paper perpetual motion machine. Most people finally began to think calmly.
Only after more than 20 years, American-born Benjamin Thomson (1753 ~ 18 14, better known as the Earl of Renford, was sealed after he went to England) discovered in 1798 that the heat generated when drilling metal made water boil. The following year, David of Britain (1778 ~ 1829) also found that rubbing two pieces of ice with a clock in a vacuum can melt into water. This experiment of "heat and phlogiston are buried in the same tomb" obviously links the transformation of thermal energy and mechanical energy. Thomson also put forward the rough mechanical equivalent of heat for the first time through experiments. Then, after the battery was invented by Italian Volt in 1800, people discovered the electromagnetic phenomena of thermal effect and magnetic effect of current. In this way, the research on the relationship between electricity, magnetism and heat has also begun. In addition, the biological world has also proved that the energy of animals to maintain body temperature and carry out mechanical activities is related to the chemical energy of food intake. In this way, by the first half of the19th century, people had initially realized the transformation and correlation among various energies such as force, heat, light, electricity, magnetism and chemical energy.
At the same time, during this period, small-scale industries are in transition to large-scale machinery industries. The research and utilization of various power equipment has prompted people to get rid of the unrealistic fantasy of "perpetual motion machine" and turn to study the energy source and transformation of machine work in a down-to-earth manner.
In this way, due to the lessons of the failure of perpetual motion machine and the achievements of studying various energies due to the actual needs of production, the prelude to the discovery of the law of conservation of energy was played, followed by the establishment of the law of conservation of energy in the first half of the ninth century and the understanding of it in the second half of the ninth century.
In the history of science, it is not uncommon for people to make another achievement because of one mistake. It gives us beneficial enlightenment: nature is full of dialectics, so we don't have to worry about making inevitable mistakes sometimes.
The law of conservation of energy has been recognized as truth. However, truth is relative, not immutable. Some people think that it is the law obtained from a large number of experiments, and some experiments cannot establish a truth because there is no strict logical proof; Especially in the microscopic field, more experiments are needed to confirm it. Therefore, although people have not found any signs that this law is not established or not revised, we should not be surprised if it is expanded and revised until it is overthrown one day. 1998 claimed that the speed of light can become very slow when it is close to absolute zero, and then it was measured in 1999 that the speed of light can be as slow as 17 m/s, which is tantamount to shaking the foundation of one of the two principles on which Einstein's special theory of relativity depends-the principle of constant speed of light. In addition, around 1962, China mathematician Hua's research on the mathematical basis of special relativity, Matthews' and Sandage's discovery of quasars in 1960, and the subsequent research on the outward expansion speed of quasars' sub-sources as high as 10 times the speed of light all thought that superluminal might exist. Even the "constant speed of light" may be denied or modified, so what is impossible?