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Edison, Thomas Alva Thomas Alva Edison (1847-1931) was an American inventor (also known as the Wizard of Menlo Park) whose many inventions revolutionized the world. His work includes improving the incandescent electric light bulb and inventing the phonograph, the phonograph record, the carbon telephone transmitter, and the motion-picture projector.
Edison's first job was as a telegraph operator, and in the course of his duties, he redesigned the stock-ticker machine. The Edison Universal Stock Printer gave him the capital ($40,000) to set up a laboratory in Menlo Park, New Jersey, to invent full-time (with many employees). Edison experimented with thousands of different light bulb filaments to find just the right materials to glow well, be long-lasting, and be inexpensive. In 1879, Edison discovered that a carbon filament in an oxygen-free bulb glowed but did not burn up for quite a while. This incandescent bulb revolutionized the world. |
Einstein, Albert Albert Einstein (1879-1955) was a German/American physicist. He revolutionized our conception of the universe with his Theories of Special and General Relativity. Special relativity supplanted Newtonian mechanics, yielding different results for very fast-moving objects. The Theory of Special Relativity is based on the idea that speed has an upper bound; nothing can pass the speed of light. The theory also states that time and distance measurements are not absolute but are instead relative to the observer's frame of reference. Space and time are viewed as aspects of a single phenomenon, called space-time. Energy and momentum are similarly linked. As a result, mass can be converted into huge amounts of energy, and vice versa, according to the formula E=mc2. General Relativity expands the theory to include acceleration and gravity, both of which are explained via the curvature of space-time. Einstein won the Nobel Prize in 1921 for explaining the photoelectric effect. His theories explained the perturbations in the orbits of Mercury. |
Estevanico Estevanico (pronounced es-tay-vahn-EE-co), also called Estevan, Esteban, Estebanico, Black Stephen, and Stephen the Moor (1500?-1539) was a Muslim slave from northern Africa (Azamor, Morocco) who was one of the early explorers of the southwestern United States. For more information on Estevanico, click here. |
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