Permanent magnet or electromagnet? Which one is best for a magnetic generator?
To understand it, you need to see what a magnet is
What Is A Magnet?
A magnet is any object that creates a magnetic field.
Magnets are the object that have a north and a south pole. They have electrons that have both uneven spin and uneven orbits.
Every magnet has at least one north and one south pole. We usually say, magnetic field line leave the north and enter the south of the magnet.
Even if you break the big bar of the magnet into two pieces, then still each piece has its own north and south pole. It doesn’t matter how small the size of the magnet is, a north and a south pole exist in every and at any size of the magnet.
All magnets created with a group of metals called ferromagnetic metals. Most of the time, these metals are nickel and iron.
The major difference between temporary and permanent magnet is, temporary magnet loses their magnetic field and get back to their original state.
The most common way these magnets made is by heating ferromagnetic metals at a Curie temperature or beyond. Curie temperature is the temperature in which ferromagnetic metals start gaining their magnetic field. Heating ferromagnetic metals at their given temperature make it magnetic for a while. However, heating beyond that temperature makes magnetism permanent.
Ferromagnetic metals categorized in soft or hard metals. Soft metals likely to lose their magnetic field overtime after being magnetized however, hard metals are likely candidates of becoming a permanent magnet.
What Are Electromagnets?
An electromagnet is a magnet that runs on electricity. Unlike permanent magnets, the strength of the electromagnet can change by changing the amount of electric current that flows through it. The poles of an electromagnet can also reverse by changing the flow of electrical current.
The electromagnet creates a magnetic field when electric current flows through it. The magnetic fields generated by the flow of electricity creates a circle around electric current as shown in the picture.
Electromagnet is pretty simple. Usually, a conductive wire (copper) wrapped around the piece of metal. An electric current is introduced through a battery or another source that produces a magnetic field. An electromagnet is useful because you can turn on or off by making or breaking the circuit respectively.
Before we go into further details about the difference between permanent and electromagnet, I would like to tell you something very quickly about magnets.
As we all know, magnet has two poles, north pole and south poles. Like poles repel each other while the opposite poles attract each other. If you bring north poles of two magnets closer to each other, they will repel. However, if you bring the north pole of one magnet closer to the south pole of another magnet then they will attract. Electromagnets work in similar fashion except they work when electric current flows through them.
A doorbell is the perfect example of an electromagnet. Electromagnet use in devices where the use of permanent magnet makes no sense.
Permanent Magnet VS. Electromagnet: What Are The Difference?
A permanent magnet as its name suggests is a ‘permanent’ magnet. It is made when ferromagnetic metals heat up beyond their temperature. Permanent magnet shows their magnetic behavior all the time.
An electromagnet is made from a coil of wire that acts as a magnet when electric current flows through it. This coil of wire wrapped around ferromagnetic material like steel that enhances the magnetic fields produced by the wire coil.
Permanent Magnet VS. Electromagnet: Magnetic Properties
A permanent magnet’s magnetic properties exist when it is magnetized. However, an electromagnet displays magnetic properties when electric current flows through it. This is how you differentiate between the two.
The magnet you affixed your refrigerator door is a permanent magnet, while the magnet used in the doorbell is an electromagnet.
Permanent Magnet VS. Electromagnet: Magnetic Strength
The strength of a permanent magnet determines with the material used in the creation of the magnet. While the strength of an electromagnet can be adjusted by adjusting the electric current that runs through it.
Permanent Magnet VS. Electromagnet: Loss Of Magnetic Properties
Permanent magnet and electromagnet both lose their magnetic properties.
A permanent magnet loses its magnetic field when heating to its maximum level. It loses its magnetic fields and become useless until it is again re-magnetized.
Electromagnet loses its magnetic field every time the electric current is removed but gains its magnetic fields back when the electric circuit is introduced.
Permanent Magnet VS. Electromagnet: Advantages
The main advantage of a permanent magnet is that a permanent magnet doesn’t need a continuous supply of electric current to maintain its magnetic field.
However, the main advantage of an electromagnet is that the magnetic fields of an electromagnet can be multiplied to a wide range by adjusting the electric current supplied to the electromagnet. This is the principle that is used in the magnetic generator to multiple energy so that it becomes enough energy to power household appliances.