St. Mary's High School, Manhasset, NY
**Important Disclaimer **
(Written by Michael H. typed by Jennifer K.)
To understand the role of magnetism in an electric motor, you have to understand what an electromagnet is. An electromagnet is a coil of wire wound around an iron core that produces magnetism as long as an electric current flows through it. This magnetism creates a force to do work. The principal utilized in motors dates all the way back to 1819 when the Danish physicist Haus Christian Oerstad produced that the first electric motor. Electric motors are classified as AC and DC, which stands for alternating and direct current.
Electromagnetic motors are so important because they are a big part of everyday life and industries and factories. Without electromagnetic motors we wouldn’t have half the luxuries we have today. Some examples of common things that use electromagnetic motors are: clocks, clothes dryers, fans, vacuum cleaners, washers, the starters of cars and windshield motors. So if you think about it, without all of these things you would not be able to tell time, you wouldn’t be able to drive a car, clean your clothes or house and much more.
(Written by Arev V., Typed by Jennifer K.)
Electromagnetic motors are used in appliances around the house. Such examples of these appliances are the telephone, the buzzer on a doorbell, the motor. The electromagnet is a loop of wire that has been coiled around an iron core and connected to the two ends of a battery. The connection of the battery and the iron core produces a magnetic field. The loop of the wire is actually the part of the part of the electromagnet that acts like the magnet.
An electromagnet is constructed with the combination of the iron core and the battery. An electromagnet's strength can be changed by increasing the number of coil turns or by adding more electricity to the source. An electromagnet can be turned both on and off by switching the controls of the current. It consists of a material that has been magnetized and then surrounded by a coil in which a current that is electric passes through it to magnetize the core.
Friedhoffer, Robert. Magnetism and Electricity. Franklin Watts Library Edition, New York: 1992.
Wong, Ovid K. Experimenting with Electricity and Magnetism. Venture book, New York: 1993.
Encyclopaedia Britannic: Micropaedia. Encyclopaedia Britannica, Inc., Chicago: 1988.