The Electromagnetic Motor
Physicists in the early 1820s began to realize the connection between electricity and magnetism, that they are really the same phenomenon. Joseph Henry was an American scientist who began experimenting with this relationship and soon discovered the usefulness of inductance (Joseph). A coiled current carrying wire generates a local magnetic field, just as a permanent magnet does. Henry wound the wire around a metal bar, so the magnetic field aligned the metal’s dipoles creating the first electromagnet. His work was published in the American Scientific Journal and it’s thought that he made the strongest magnet to date (capable of lifting 750 pounds) (Joseph). He quickly improved his models to support over 2,000 pounds of weight.
Understanding the electromagnet was the foundation for the electric motor. In the same way that electric current was able to induce a magnetic field, a magnetic field can induce an electric current. Joseph Henry created the first electromagnet motor, using two permanent magnets to rotate the electromagnet (Joseph). The process required some electric potential (such as a chemical battery) to maintain proper magnetic pole orientation, but nevertheless this was the first time that stored electric and magnetic were transformed directly into mechanical work, serving as a precursor to the modern DC (direct current) motor.
The electromagnetic motor aided advances in electric communication, such as the telegraph, further shrinking the size of America. It also broke some major theoretical ground that would allow America to one day be connected by an electric grid.
Understanding the electromagnet was the foundation for the electric motor. In the same way that electric current was able to induce a magnetic field, a magnetic field can induce an electric current. Joseph Henry created the first electromagnet motor, using two permanent magnets to rotate the electromagnet (Joseph). The process required some electric potential (such as a chemical battery) to maintain proper magnetic pole orientation, but nevertheless this was the first time that stored electric and magnetic were transformed directly into mechanical work, serving as a precursor to the modern DC (direct current) motor.
The electromagnetic motor aided advances in electric communication, such as the telegraph, further shrinking the size of America. It also broke some major theoretical ground that would allow America to one day be connected by an electric grid.
Sources:
The Joseph Henry Papers Project. The Joseph Henry Papers Project. Retrieved April 11, 2014, from http://siarchives.si.edu/history/jhp/joseph21.htm
The Joseph Henry Papers Project. The Joseph Henry Papers Project. Retrieved April 11, 2014, from http://siarchives.si.edu/history/jhp/joseph21.htm