Permanent Magnets vs. Electromagnets: Performance Comparison and Applications
A basic law of nature, magnetism is applicable in several ways into our lives. Magnets have become part of everything we use from the compass that shows us direction to hard drives that store our digital lives. There are two main types of magnets: permanent magnets and electromagnets. The article will consider their performance and discuss their applications.
Permanent Magnets
These magnets make a magnetic field themselves and have been therefore named “permanent”. Their properties as magnets don’t change even when there is no external source or current causing it to do so. For instance, most common permanent magnets are made from iron, nickel, cobalt and some rare earth metals.
Performance
The fields from these permanent magnets remain consistent. They consume low power since they are not externally powered. However, this magnetic strength cannot be adjusted; besides, these can be demagnetized when they come in contact with high temperatures or stronger magnetic fields.
Applications
In many cases, permanent magnets serve different purposes for various institutions. Simple samples include fridge stickers/compasses whereas complex ones involve electric motors/generators/magnetic resonance imaging (MRI).
Electromagnets
Unlike permanent magnetized substances which create a magnetic field only when an electric current flows through them; this implies that such magnetism can be switched on/off while increasing/decreasing its intensity by changing the value of the current flowing through it.
Performance
Controllability is one of the merits associated with electromagnets. It is very easy to adjust their magnetic fields by regulating electric currents running through them. Nevertheless keeping up a continuous power supply so as to sustain a magnetic field leads to heavy energy consumption and heat production.
Applications
There are various examples where electromagnet may find application including electric motors, transformers, trains powered by magnetic levitation system as well as at junkyards where scrap metal is lifted using cranes.
Conclusion
Both permanent magnets and electromagnets have their unique advantages and are suited for different applications. Permanent magnets are energy efficient, generate stable magnetic fields and are therefore preferred for applications requiring a steady magnetic field. However, an electromagnet can be used wherever the magnetic field needs to be controlled in that its magnitude is adjustable. In various applications, it is necessary to understand the distinctive properties of these two types of magnetism.
