An electromagnetic motor is a machine that uses the magnetic forces produced by a wire with flowing electricity to power the movement of the motor. All electric motors operate on electromagnetic principles. Types of electric motors include alternating current (AC) motors and direct current (DC) motors. AC motors use wall current and DC motors use a battery as a source of power and magnetic forces to spin the motor. The electromagnetic motor is common in nearly every household, frequently found in popular household items such as fans, pool pumps, air conditioners, washing machines, and electric toothbrushes.
The rotating motion of an electromagnetic motor is based on the forces observed in magnetic poles. A magnet hung from a string in the center will naturally rotate to face one end to the north and one end to the south. The magnetic poles located on each end of the magnet attract if the poles are opposite and repel if the poles are alike. When two north pole magnets are brought within the fields of the magnets’ force, the magnets will push away from each other. If one north pole and one south pole are brought together, they will attract and stick to each other.
Though electromagnets used for science experiments in class are typically wires wrapped around a small stick of iron, a properly coiled conductive wire can become an electromagnet when supplied with current. The force becomes amplified when the wire is coiled. Magnetic force from a wire coil with current becomes stronger yet when the coil is wrapped around an iron magnet.
Electric current running through a wire produces a magnetic field, so electromagnetic force is present in wires with current running through them. Consequently, a wire with electric current running through it has an inherent magnetic force. When that wire is coiled into multiple parallel loops, it takes on the properties of a magnet when current runs through it. Wires not intended for use as electromagnets are often shielded to dampen the magnetic force and reduce its interference with other nearby electronics.
Some types of electromagnetic motors can be propelled with no electrified iron-core magnet, using only the magnetic force from carefully arranged coiled wires. Usually, electromagnetic motors have one or more iron-core electromagnets powering the movement of the motor. Though an electromagnet created with a magnetic core is more powerful, it also draws more electricity, putting more demand on the power source and draining batteries more quickly. High-powered electromagnetic motor assemblies sometimes use more than one electromagnet in the motor to give the motor a controlled power boost.