What is a permanent magnet?

Permanent magnet is a magnet that is permanent, unlike an electromagnet that behaves like a magnet only when electric current flows. Permanent magnets are made of substances such as magnetite (Fe _{3 4 ), the most naturally occurring mineral or nestylium, a strongly magnetic synthetic substance. The Earth itself is a huge permanent magnet, although its magnetic field is relatively weak due to its size. People used the Earth's magnetic field to navigate because the compass was invented in ancient China.}

or the strongest permanent magnet is not as strong as stronger electromagnets, so their applications are limited, but still have many uses. Most secular would be to use as refrigerator magnets, but magnets can be found everywhere, including your hard disk, ATMs and credit cards, speakers and microphones, electric engines and toys. Electric motors work through interaction between Electromagnet and permanent mAgnet.

Every permanent magnet generates a magnetic field, as well as any other magnet that circulates around the magnet is a clear pattern. The magnetic field is related to the magnet size and its strength. The easiest way to display a magnetic field generated by a permanent magnet is to disperse iron administration around a bar magnet that quickly navigates along the lines of the field.

Every permanent magnet has two poles, named north and south, although they could be equally easily called A and B. Similar poles repel while attracting the opposite poles. It takes a lot of effort to hold the poles of the magnet together while the effort to remove the attraction of the poles. The strongest magnets attract so hard that they can cause injury by clamping the skin between them.

For thousands of years, permanent magnets were the only magnets that people had. Electromagnet was invented only in 1823. Previously, magnets were mostly news. Using an electromagnet, it is possible to induce current in any ferromagnetic materials such as an iron clip. However, the effect disappears rapidly.

Permanent magnets can be harassing by threatening to delete data from ATM cards or hard drives. A common way to delete data from the computer's hard disk and ensure that it is irreparable is to start the magnet above it. Otherwise, the "removed" files are actually on the computer, only hidden. This is because there is more work for the computer to actually delete data. Rather, the data is marked as a hard disk sector that can be written without fear.