Because magnetism is a force, magnets can be used to move things. Electric motors convert the energy of an electric current into motion by taking advantage of the interaction between current and magnetism.
There are hundreds of devices that contain electric motors. Examples include power tools, electrical kitchen appliances, and the small fans in a computer. Almost anything with moving parts that uses current has an electric motor.
All motors have similar parts and work in a similar way. The main parts of an electrical motor include a voltage source, a shaft and electromagnet, and at least one additional magnet. The shaft of the motor turns other parts of the device.
Recall that an electromagnet consists of a coil of wire with current flowing through it. When current from the voltage source flows through the coil, a magnetic field is produced around the electromagnet. The poles of the magnet interact with the poles of the electromagnet, causing the motor to turn.
1)The poles of the magnet push on the like pole sof the electromagnet, causing the electromagnet to turn.
2) As the motor turns, the opposite poles pull on each other.
3) When the poles of the electromagnet line up with the opposite poles of the magnet, a part of the motor called the commutator reverses the polarity fo the electromagnet Now, the poles push each other again the the motor continue to turn.
The illustration at the bottom of the page is simplified so that you can see all the parts. If you saw the inside of an actual motor, it might look very different. THe wires coil many times. The electromagnet is a strong motor may coil hundreds of times. The more coils, the stronger the motor.
Uses of Motors
Many machines and devices contain electric motors that may not be as obvious as the motor that turns the blades of a fan, for example. Even though the motion produced by the motor is circular, motors can move objects in any direction. For example, electric motors move power windows in a car up and down.
Motors can be very large, such as the motors that power an object as large as a subway train. They draw electric current from a third rail on the track or wires overhead that carry electric current. A car uses an electric current to start the engine. When the key is turned, a circuit is closed, producing a current from the battery to the motor. Other motors are very small, like the battery operated motors that move the hands of a wristwatch.