Tesla believed that alternating current was vastly superior to (Edison's) direct current. Alternating current is practical because of the fact that it can be converted to suit a variety of situations. For example, if the voltage is made quite high, then the current necessary for a specific level of power is very low. This low current then becomes very efficient when sending electrical power over very long wires.
Tesla also worked with radio-frequency electromagnetic waves, and despite the claims made by Marconi, actually did invent the idea of Radio as we know it today. In working with radio waves, he created the Tesla coil (see link below) as a means to generate and receive this form of energy.
When Tesla died in 1943 he held over 700 patents.
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In 1644 he performed the famous barometric experiment that enabled him to demonstrate the existence of atmospheric pressure.
Torricelli's only published work was Opera geometrica, 1644, which included work on motion (or mechanics). Torricelli was also the most gifted lens grinder of his age, who made many telescopes and who developed a microscope using tiny drops of crystal the size of a grain of millet.
On his first expedition, he was the navigator for Alonzo de Ojeda. They left Spain in 1499 and discovered the mouth of the Amazon River in South America. On his second expedition to the New World, he mapped the eastern coast of the New World, and realized that they were not in Asia, but a totally different, unknown continent.
America was named after him in 1507, when the German cartographer, Waldseemueller, printed the first map using the name Amerigo for the New World.
By 1800 he had developed the so-called voltaic pile, a forerunner of the electric battery, which produced a steady stream of electricity. The electrical unit known as the volt was named in his honor.
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