To completely comprehend their usefulness, we must first understand some basic information on them. Magnets are objects that attract other matter containing iron or steel. Magnet typically has two poles: north and south. Have you ever touched two magnets together? You should try this! You'll notice that when you touch the like poles of the magnets together they actually push away each other, and when the opposite poles touch each other the magnets stick together. Magnets have their strongest capabilities at their poles.
As a matter of fact, magnets are so powerful that they can pass through many materials. That's why we're able to display our great school work on our home refrigerator using magnets. The magnet's force is able to pass through paper.
While all magnets share the concept of generally having two poles, magnets can differ. Temporary magnets and permanent magnets are the two types of magnets. They differ in one simple way; while permanent magnetshold onto their magnetic capabiliites for long durations, temporary magnets lose their magnetic capabilities over time.
Permanent magnets are typically made up of iron, nickel, and cobalt. Since these are the only three metals that can be magnetized, they are known as "hard magnetic materials." On the other hand, electromagents are examples of temporary magnets. These are formed by electric currents. Temporary magnets have poles as well. "One end of the solenoid becomes the north pole of the electromagnet and the otehr end the south pole." Its magnetism capabilities are dependent upon the current. If the current switches directions, then so does the poles. Once the current is stopped, the electromagnet loses its magnetism. The most powerful electromagnets are called hybrid magnets.
Whether or not a magnet is temporary or permanent it is attracted to items that consist of iron or steel. Did you know that you can create a magnet? If you were to rub a magnet against a metal (ex. nail) in the same direction it would become magnetized (at least for a short period of time).
We have gained so much information on magnets and magnetism, because of great scientists. Scientists such as Hans Christian and Andre Marie have proven that magnetism and electricity are related in some ways. Pierre Curie has even proved that when magnets reach a particular temperature they lose their magnetism. As time goes on there are sure to be future scientists to discover other capabilities or information pertaining to magnets.