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Electricity History

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Electricity History Electricity History Name Year Contribution Thales of Miletus 600 B.C. Discovered that amber, after being rubbed, has the property of attraction over certain objects. Image 6.1 Amber Image obtained from http://www.electricasas.com/wp-content/uploads/2009/04/electrost1.jpg For educational purposes only Name Year Contribution William Gilbert 1600 A.D. Studied magnets and was the first to use the term electricity, which comes from the Greek electron (amber). Otto von Guericke 1672 A.D. Described the first machine to produce electric charges. Francois de Cisternay Du 1733 A.D. Identified two types of charges and named them Fay vitreous and resinous. E.G. Von Kleist & Pieter Van 1745 A.D. Leyden bottle was developed to store static electricity, Musschenbroeck important to the future development of the condenser. (Leyden University) Benjamin Franklin 1752 A.D. Invented the lightning rod and explained electricity as a flow of mass. Joseph Priestley 1766 A.D. Demonstrated that force between two charges varies inversely to the distance between them. Charles Augustin Coulomb 1776 A.D. Measured the force between charges with a torsion balance and observed that it is equal to the product of the individual charges and inversely proportional to the square of the distance between them. Image 6.2 Lightning rod types Image obtained from http://programacasasegura.org/mx/para-usted/luces-en-el-cielo/ For educational purposes only Name Year Contribution Alessandro Volta 1800 A.D. Invented the battery with a chemical cell capable of providing continuous current. Sir Humphry Davy 1801-1815 Developed electrochemistry. A.D. Simeon Denis Poisson 1812 A.D. Described electrostatic laws. Hans Christian Oersted 1819 A.D. Discovered electromagnetism. Biot & Savart 1820 A.D. Discovered how to calculate the force exerted by a field over an electric charge and defined the intensity of magnetic field. André-Marie Ampére 1823 A.D. Established electrodynamics principles. Georg Simon Ohm 1826 A.D. Established the electric current law defining the exact relation between tension and current. George Green 1828 A.D. Enriched Poisson’s work obtaining the general solution for calculating potential. Joseph Henry 1828 A.D. Perfected electromagnets, developed self-inductance concept. Michael Faraday 1831 A.D. Electricity can be produced by movement. He concluded that tension can be induced by moving a coil in a non- uniform magnetic field. Samuel F. B. Morse 1835 A.D. Used the electromagnetism principles to make the first telegraph. James Prescott Joule & 1840-1842 Electric circuits satisfy the law of conservation of Ludwig Ferdinand Helmholtz A.D. energy; electricity is a form of energy. Gustav Robert Kirchhoff 1845 A.D. Announced the laws to calculate tensions and currents in electric networks. William Staite 1847 A.D. Introduced arc lamps. Image 6.3 Morse Telegraph Image obtained from http://electronica.webcindario.com/glosario/telegraf.htm For educational purposes only Name Year Contribution William Thomson Kelvin 1854 A.D. Studied the transfer of electricity by cable and defined the second law of thermodynamics. Julius Plucker 1859 A.D. Discovered cathode rays. Zenobe-Theofile Gramme 1868 A.D. Machine of continuous current. James Clerk Maxwell 1870 A.D. Formulated equations of electromagnetic theory. Alexander Graham Bell 1876 A.D. Invented the telephone. Joseph John Thomson 1879 A.D. Named electrons as corpuscles. Thomas Alva Edison 1881 A.D. Produced the first incandescent lamp. Hertz 1884 A.D. Demonstrated the validity of Maxwell equations and gave the basis to develop the radio. John Henry Poynting 1884 A.D. Demonstrated the relation between electric and magnetic field by an equation, called Poynting vector. Nikola Tesla 1888 A.D. Developed the theory that allowed the improving of alternating current generators and motors. George Westinghouse 1895 A.D. Bought the rights to Tesla and put into service the first plant to produce electricity. Image 6.4 Alternating current motor of Nikola Tesla Image obtained from http://www.bibliotecapleyades.net/tesla/esp_tesla_28.htm For educational purposes only .
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