美国英语听力80篇3 Lesson51
Nikola Tesla
Nikola Tesla developed the alternating current power system that provides electricity in the United States.
Many of his other discoveries led to electronic inventions for which other scientists were honored.
Mister Tesla held more than 100 patents given by the United States government.
A patent gives the inventor the right to make, use and sell his invention for a period of time
Nikola Tesla was born in what is now Croatia in 1856.
He began inventing when he was a child.
He later studied to be an electrical engineer.
He moved to the United States in 1884, He became an American citizen five years later.
Nikola Tesla received a patent for his alternating electric power system in 1888,
He was working in his own laboratory in New York City.
George Westinghouse bought the patent rights from Mr Tesla.
Then Mister Westinghouse launched the campaign
that established alternating current as the electric power system in the United States.
What is alternating current?
The electricity used in a light bulb, for example, comes from a power center that may be kilometers away.
The strength of the electric power would become weak if it traveled a long distance at the same level.
Alternating the strength of the current keeps it strong.
The current changes from negative to positive sixty times each second.
Mister Tesla also invented a device known as the Tesla Coil.
It is the basis for radio, television and other means of wireless communication.
He also invented a kind of light bulb and the X-ray machine.
Mister Tesla created a general design for radio,
but was not recognized for it during his life.
He did the work in 1892.
Guglielmo Marconi later claimed the patent rights.
Mister Tesla made an unsuccessful attempt to oppose Mister Marconi's claims in 1915.
It was not until 1943 that the United States Supreme Court ruled that Mister Tesla was the legal inventor of radio.
Nikola Tesla had died a few months earlier.
He and his work had been forgotten by the public.
Experts say he was not recognized because of several reasons.
He failed to market his inventions.
He made enemies of powerful men.
Many of his later ideas were considered to be very strange,But experts say the world has changed since then,
