#children's story# Introduction Suffering and setbacks are a fortune in life. After experiencing the ups and downs of life, you will know how to cherish it. The following is a short celebrity story compiled and shared. Welcome to read and learn from it. I hope you will Will like it!
Edison invented the electric light
Edison began experiments to reform the arc lamp in 1877, proposing to divide the current and convert the arc lamp into a white light lamp. This test needs to be done satisfactorily. It is necessary to find a substance that can burn to white heat to make a filament. This filament must withstand burning at a temperature of 2,000 degrees for more than 1,000 hours. At the same time, it should be simple to use, able to withstand the bumps and bumps of daily use, and the price should be low. The turning on and off of one lamp should not affect the turning on and off of any other lamp, and the relative independence of each lamp should be maintained. In order to choose this kind of lamp. This was a very bold idea at the time and required great efforts to explore and test. As for the material used for filament, Edison first experimented with carbonized substances. After failure, he experimented with metal platinum and iridium high-melting-point alloys. He also conducted 1,600 different experiments on high-quality ores and ore seedlings. The results All failed. But by this time, he and his assistants had made great progress and knew that the incandescent filament must be sealed in a highly vacuumed glass sphere to prevent it from melting. In this way, his experiments returned to carbon filaments. He worked day and night until the first half of 1880, but Edison's incandescent lamp experiment still had no results. One day, he tore a piece of bamboo silk tied to the edge of a banana fan in the laboratory into thin filaments, and devoted all his energy to carbonization. There were more than 6,000 carbonization experiments on plants alone. He has more than 200 experimental notebooks, totaling more than 40,000 pages, which took three years to complete. He works eighteen or nineteen hours a day. At three or four o'clock every morning, he would sleep under the experimental table with two or three books on his head. Sometimes he slept on the stool three or four times a day, for just half an hour each time.
By the first half of 1880, Edison's incandescent lamp experiments still had no results, and even his assistants were discouraged. One day, he tore a piece of bamboo silk tied to the edge of a banana fan in the laboratory into filaments, and then carbonized it to make a filament. The result this time was better than all the previous experiments. This was Edison's earliest experiment. The invention of the incandescent electric lamp - the bamboo filament electric lamp. This bamboo filament electric lamp continued for many years. It was not replaced until the invention of tungsten filament in 1908. The alkaline storage battery that Edison began to develop after this was very difficult, and his research spirit was even more amazing. This kind of battery is used to provide motive power. He and a selected assistant worked painstakingly for nearly ten years and experienced many hardships and failures. One moment he thought he had reached his destination, but the next moment he knew he was wrong. But Edison never wavered and started over. After about 50,000 experiments and more than 150 test notes were written, the goal was achieved.
As we all know, Thomas Edison was a great inventor who always achieved success in his life. With 1,093 invention patents, he is the person who has obtained the most personal patents since the introduction of the patent system. His famous saying "Genius is ninety-nine percent hard work and one percent inspiration" has become a motto that inspires people to work hard. It can be said that Edison's contribution greatly changed human life. Of his many inventions, Edison considered the electric light the most important, but his favorite was the phonograph. The following is the process of the invention of electric light: Lamp is a great invention for mankind to conquer the night. Before the 19th century, people generally used oil lamps, candles, etc. for lighting. Before the advent of electric lights, the most commonly used lighting tools were kerosene lamps or gas lamps. Although this has broken through the night, it has not yet completely liberated mankind from the restrictions of the night. Only the birth of the generator enabled human beings to use various electric lights to brighten the world, turn night into day, expand the scope of human activities, and gain more time to create wealth for society.
At the beginning of the 19th century, a British chemist made the world's first arc lamp. But this kind of light is too strong and can only be installed on streets or squares, and cannot be used by ordinary families. Countless scientists have racked their brains to create a cheap, high-quality, durable household electric light. The day has finally arrived. On October 21, 1879, an American inventor finally ignited the world's first practical electric lamp through long and repeated experiments. Since then, the name of this inventor, like the electric light he invented, has entered thousands of households.
He was Edison, who was praised as the "King of Invention" by later generations.
Edison was an extremely diligent person who liked to do various experiments and created many ingenious machines. He was particularly interested in electrical appliances. Since Faraday invented the motor, Edison was determined to create electric lights and bring light to mankind.
In the process of inventing the electric light, Edison carefully summarized the failed experience of his predecessors in making electric lights. He experienced countless failures, but he was not discouraged and finally turned cotton yarn into charred charcoal. He carefully put the carbon filament into the glass bubble and tested it. The effect was indeed very good. The life of the light bulb was suddenly extended by 13 hours, and later reached 45 hours. In this way, the world's first carbon filament incandescent lamps came out. On New Year's Eve 1879, Lopack Street, home to the Edison Electric Light Company, was brightly lit. Finally, Edison put the carbonized bamboo filament into a glass bulb. After powering on, the bamboo filament bulb lit up continuously for 1,200 hours!
The carbon filament electric lamp invented by Edison is similar to the one invented by Edison. Compared with the arc lamps of the past, they are undoubtedly much more practical. Its appearance marked the official beginning of the history of human use of electric lights. However, the brightness of this kind of carbon filament electric lamp is not ideal, the production method of the filament is relatively complicated, and the service life is not very long. Therefore, scientists from all over the world are working on improving incandescent lamps.
In 1909, 30 years after the birth of the carbon filament electric lamp, Kulicki of the General Electric Company of the United States invented an electric light bulb with tungsten filament. This kind of electric lamp is a step forward compared with carbon filament electric lamps, but because the tungsten filament easily becomes brittle after being energized, its service life is also affected.
Ohm and Ohm’s Law
George Simon Ohm was born in Erlangen, Germany. His father was a locksmith. His father taught himself mathematics and physics and taught it to Ohm as a boy, arousing Ohm's interest in science. At the age of 16, he entered the University of Erlangen to study mathematics, physics and philosophy. Due to financial difficulties, he dropped out of school and did not complete his doctoral studies until 1813. Ohm was a man of great genius and scientific ambition. He had been a middle school teacher for a long time. Due to the lack of materials and instruments, it brought many difficulties to his research work, but he always persisted in scientific research in a lonely and difficult environment. Research and make your own instruments.
Ohm studied the current in a wire. He was inspired by the heat conduction law discovered by Fourier. The heat flow between two points in the heat-conducting rod is proportional to the temperature difference between the two points. Therefore, Ohm believed that the phenomenon of electric current was similar to this, and speculated that the current between two points in the wire may be proportional to some driving force between them, which is now called electromotive force. Ohm spent a lot of energy on research in this area. At first he used a voltaic pile as a power source, but the effect was not good because the current was unstable. Later, he accepted others' suggestions and switched to using a thermoelectric battery as the power source, thereby ensuring the stability of the current. But how to measure the magnitude of the current was still an unsolved problem at the time. At first, Ohm used the thermal effect of electric current to measure electric current using the method of thermal expansion and contraction, but this method was difficult to obtain accurate results. Later, he combined Oersted's discovery of the magnetic effect of current with the Coulomb torsion scale, and cleverly designed a current torsion scale, using a twisted wire to suspend a magnetic needle, so that the current-carrying wire and the magnetic needle were placed parallel to each other along the meridian direction; Use a bismuth and copper thermoelectric battery, immerse one end in boiling water and the other end in crushed ice, and use two mercury tanks as electrodes connected to copper wires. When a current flows through the wire, the deflection angle of the magnetic needle is proportional to the current in the wire. He published the experimental results in 1826. In 1827, Ohm summarized his experimental rules into the following formula in his book "Mathematical Research on Circuits": S=γE. In the formula, S represents the current; E represents the electromotive force, that is, the potential difference between the two ends of the wire, γ is the conductivity of the wire to current, and its reciprocal is the resistance.
In the early days of the discovery of Ohm's law, many physicists were unable to correctly understand and evaluate this discovery, and were met with skepticism and sharp criticism. The research results were ignored and the economy was extremely difficult, which made Ohm mentally depressed. It was not until 1841 that the British Royal Society awarded him the honorary Copley Gold Medal, which attracted the attention of the German scientific community.
Ohm also proved in many of his works that resistance is directly proportional to the length of the conductor and inversely proportional to the cross-sectional area and conductivity of the conductor; in the case of a stable current, the charge is not only on the conductor on the surface and across the entire cross-section of the conductor.
To commemorate him, people named the physical quantity unit for measuring resistance after Ohm.
I am the first person to come to the earth from an alien planet
There are actually two astronauts who landed on the moon for the first time. In addition to the well-known In addition to Armstrong, there is also Odrun. What Armstrong said at that time: "One small step for me, one giant leap for mankind." has long become a household name around the world.
At the press conference celebrating the successful landing on the moon, a reporter suddenly asked Odrun a very special question: "If Armstrong goes down first and becomes the first person to land on the moon, what will you do?" Don't you feel a little regretful?"
Under the somewhat embarrassed attention of the audience, Odrun responded gracefully: "Everyone, don't forget, when I return to Earth, I am the last The one who got out of the space capsule first." He looked around and said with a smile, "So I am the first person to come to the earth from other planets."
Everyone gave him the warmest greetings while laughing. applause.