Computer is one of the most advanced scientific and technological inventions in the 20th century, which has had an extremely important impact on human production and social activities, and has developed rapidly with strong vitality.
Its application field has expanded from the initial military scientific research application to all fields of society, forming a huge computer industry, promoting global technological progress and triggering profound social changes. Computers have spread all over ordinary schools, enterprises and institutions, entered the homes of ordinary people and become an indispensable tool in the information society.
The application of computers is becoming more and more common in China. After the reform and opening up, the number of computer users in China has been increasing, and the application level has been improving, especially in the fields of Internet, communication and multimedia.
2. Artificial satellite
Man-made satellite is an unmanned spaceship, which runs around the earth in space. Satellites basically orbit the earth according to the laws of celestial mechanics, but the actual motion is very complicated due to the influence of the gravitational field, atmospheric drag, solar gravity, lunar gravity and light pressure of aspheric earth with different orbits.
Satellite launches account for more than 90% of the total number of spacecraft launches.
Satellites can be divided into three categories: scientific satellites, technical test satellites and application satellites. Scientific satellites are satellites used for scientific exploration and research, mainly including space physics exploration satellites and astronomical satellites.
It is used to study the atmosphere, radiation belt, magnetosphere, cosmic rays and solar radiation of a planet, and can also observe other stars. At present, most of the artificial satellites in the world are artificial earth satellites, and there are also artificial Mars satellites.
1957 10 After the Soviet Union launched the world's first artificial satellite, the United States, France and Japan also launched artificial satellites one after another. China launched its first artificial satellite "Dongfanghong-1" on April 24th.
3. Aircraft
An airplane is an airplane heavier than air. It has a power plant, one or more engines generate forward thrust or pull, and the fuselage has a fixed wing to generate lift.
The airplane is one of the most important inventions in the early 20th century, and it is generally believed that it was invented by the Wright brothers in America. Their flight on 1903 17 February 17 was recognized by the International Aviation Federation (FAI) as "the first controlled sustained power flight of heavier-than-air aircraft", and in the same year they founded Wright Aircraft Company.
Since the invention of the airplane, it has become an indispensable means of transportation for modern civilization. It profoundly changes and affects people's lives. Due to the invention of the airplane, the time for human beings to travel around the world has been greatly shortened.
The first round-the-world trip was completed in16th century. At that time, the Portuguese Magellan led a fleet from Spain, which took three years to cross the Atlantic and Pacific oceans, circle the earth and return to Spain.
/kloc-At the end of 0/9, it took a Frenchman 43 days to travel around the world by train. After the invention of the airplane, people made another round-the-world trip at 1949.
A B-50 bomber flew 37,700 kilometers around the earth in just 94 hours after four beautiful aerial refueling. It is better to be strong than not. After the supersonic plane appeared, people flew higher and faster.
1979, spector, an Englishman, flew 36,900 kilometers and circled the earth in only 14 hours and 6 minutes. In less than a day, you can fly to every corner of the earth, which can be said to be a miracle for human beings who lived before the 20th century.
4. electric light
1858, British Swan made the world's first carbon filament lamp. 1878, Edison invented a better light bulb, 1879, Edison invented an electric lamp that can continuously illuminate 1000 hours. 19 13, after the tungsten wire was patented, the electric light began to light up.
5. Satellite TV
The inventor of TV set is john baird, a British electronic engineer. In 1923, he applied for a patent for a device that can generate 8 lines of images. The first TV set was sold at the end of 1930.
1932, BBC broadcast the first standardized TV program in the world. Since then, mankind has begun to step into the television era. Today, people use satellites and other channels to spread TV signals to every corner of the earth.
Nowadays, the per capita possession of TV in the world is extremely high (one per 10 people on average), which started at 1927 and started in the hands of Americans.
Baidu Encyclopedia-Invention of the 20th Century