industrial electromagnet
The electromagnet is a device that transforms an electrical current into a magnetic field. This is done through a process called electromagnetic induction. Normally magnets fall into two categories. They can either be permanent or a temporary. In both cases a magnet is created when its smaller magnetic fields called domains are aligned in one direction creating a larger magnetic field. In other words most items that can become magnets aren’t because the magnetic fields point in different directions and cancel out each other. A temporary magnet is one where a magnetic force aligns the domains for a time. Afterward, the domains return to their original positions and the magnet loses strength. A permanent magnet is created when a strong magnetic field permanently aligns the domains of an iron or nickel item.
In the case of the electromagnet the process is something in between. As long as an electrical current flows through the electromagnet it has a magnetic field. If the current is disrupted the object is no longer a magnet. The process that causes this, electromagnetic induction, is a result of the unique relationship between electricity and magnetism. The existence of one creates the other. That is why physicist refer to both as one fundamental force, called the electromagentic force. Electromagnets were discovered during the 19th century but the first scientist to discover the relationship was Michael Farraday. His work would later lead to the invention of the electric generator and motor.
So how do you make an electromagnet? It is actually quite simple. First you need a power source. Other than a running electric current the likely source will be a battery. Then you need a conductor to carry the current. This will be copper wire. You also need an ferromagnetic object. This will be any item that is made of iron or nickel. Connect the wire to the battery on both of its positive and negative terminals on one side. Connect the other end of the wire to the iron or nickel object. If you are using a nail just wind the wire around it. You will immediately have an electromagnet. Of course try to use insulated wire and a switch.
Electromagnets play an important role in modern life. Without it we can’t produce electricity or make electric appliances. They also are used in industry for transportation such as high speed trains and to lift large scrap metal.
If you enjoyed this article there are other articles on Universe Today that you will like. There is a great article about wind power and another on generators.
You can also find great resources online. There is a great article on howstuffworks.com that talks about electromagnets in detail. You can also check out the Franklin Institute website.
You can also check out Astronomy Cast. Listen to Episode 145 on interstellar travel to see how electromagnets can be used in space travel.
Sources:
Wikipedia
How Stuff Works
Hyperphysics
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