Magnets have been in use for ages and their working principle has always been a cause for fascination. These simple metals hold the power to attract and repel objects explaining their extensive usage in most devices.
How Permanent Magnets Work?
To understand how permanent magnets work, it is important to first grasp what they are. Permanent magnets are distinct magnets characterized by never-ending magnetism. They also create their own magnetic field which keeps their magnetic capabilities permanent.
The Basics of Magnetism
Magnetism is a natural force responsible for the attraction and/or repulsion of objects. It arises from the alignment of magnetic moments within electrons. Magnetic moments are generated once electrons spin or move in an orbital motion.
This consequent motion results in the creation of a magnetic field. Permanent magnets owe their magnetic properties to the ferromagnetic materials they are made from. These materials contain electrons whose continued spinning leads to the creation of magnetic moments. This acts as the basis of magnetism.
A magnetic domain refers to a part of magnetic material with uniformly lined up magnetic moments. These domains are responsible for magnetic capabilities.
Subjecting a permanent magnet to a more superior magnetic field sees the magnet’s magnetic domain sync with the external field. This can elevate the magnetic powers of the permanent magnet but extreme exposure can cause magnetic saturation.
Underneath, we break down the working principles of permanent magnets:
Step 1: Electron Spin
At the basis of permanent magnets lies atoms with electrons and these electrons have a tendency to rotate or spin. This harmonious rotation leads to magnetic moments. The electrons in magnetic material tend to spin in an upward or downward direction. Electron spin eventually results in the alignment of magnetic moments within magnetic domains.
Step 2: Magnetic Domain Alignment
To make a permanent magnet, a ferromagnetic material is subjected to a robust external magnetic field. In some instances, the magnetic material is heated above the curie point and this results in the alignment of magnetic domains.
As the magnetic domains continue to align, the magnetic material becomes increasingly magnetic.
Step 3: Magnetic Field Lines
Magnetic field lines are lines that depict the direction of a magnet’s magnetic force. They usually originate from the north pole. They also determine the magnet’s magnetic field and they are formed as the magnetic domains align.
Step 4: North and South Poles
The working of permanent magnets is essentially based on the north and south poles. The magnetic field lines exit the ferromagnetic material at the north pole and they re-enter the magnet at the south pole. The poles are dictated by the magnetic domain arrangement.
Step 5: Attraction and Repulsion
Permanent magnets can either attract or repel objects depending on the make-up of the object. Like poles for instance north and north tend to repel whereas unlike poles tend to attract. The interaction of permanent magnets with other objects is often determined by the Lorentz force law.
Step 6: Retaining Magnetism
Permanent magnets are renowned for their never-ending magnetism. They retain their magnetic capabilities even after an external magnetic field has been withdrawn.
This property is due to the exchange interaction between neighboring electrons in the ferromagnetic material. This interaction keeps the magnetic domains aligned resulting in a magnetic field within the material.
You can learn more about laws of magnetism.
How Electromagnets Work?
Electromagnets are known for generating a magnetic field using electricity. They are made by enfolding a ferrous material such as iron with a conductive wire.
By controlling the amount of current passing through the wire, one can power on and off the electromagnet. Here is a breakdown of how these unique magnets function.
Step 1: Choosing the Core Material
The core material of an electromagnet is a ferrous material that can be magnetized and demagnetized easily. Most electromagnets have iron as the core material but other metals can be used instead.
Step 2: Coiling the Wire (Solenoid)
After selecting the core material, an insulated wire is coiled round the core material. Most electromagnets utilize copper wire and this is primarily because they exhibit low resistance to electrical current. Coiling the wire multiple times results in a stronger electromagnet.
Step 3: Connecting the Wire
After wrapping the wire around the core material, the ends of the wire are connected to a power source. The power source can be a battery or an electrical circuit. As power runs through the wire, the rod becomes magnetized and an external magnetic field is created.
Step 4: Generation of a Magnetic Field
Electromagnets are identified by the manner in which they generate a magnetic field. Their magnetic field is created by the electric current running through wire wrapped around the core material. In an electromagnet, the field lines tend to follow the track or direction of the current flow.
Step 5: Adjusting the Magnet’s Strength
With an electromagnet, you can regulate its strength by increasing or lowering the amount of current running through the wire. Upping the current flow will strengthen the magnetic field further whereas lowering the flow will have a reverse effect.
Step 6: Turning On and Off the Magnet
An electromagnet can be turned on and off as one wills. Connecting the wire to a power source results in the creation of a magnetic field and this turns on the electromagnet.
Disconnecting the wire from the power source results in the elimination of the magnetic field. This deprives off the core material’s magnetic properties.
Magnets are without a doubt testament to the remarkable brilliance of engineering. They are widely utilized in home appliances like loudspeakers as well as industrial machinery.
This has made them objects of interest for people interested in learning the science behind magnetism. This article has centered on the inner workings of permanent magnets as well as electromagnets with the intention of helping you harness their full power.
As you can see how magnets work is quite simple and straight forward. If you are looking for any inform about any magnet, we are here to help you get high quality magnates.