Category Archives: Categories

What is a homopolar motor and how does one work?

Neodymium disc magnets and an electromagnetic coil with AA battery

In our previous blog article we took a look at how a DC and an AC motor works and described how you can build your own basic DC motor. Even simpler than a basic DC motor, is a homopolar motor. First created in 1821, it really is the simplest example of a motor possible, and really easy to experiment with.

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Animal magnetism – Nature’s own satellite navigation system

Migrating sea turtle swimming

The Earth produces its own magnetic field, which emanates from its magnetic inner iron core. On the Earth’s surface the magnetic field is extremely weak compared to the permanent magnets used in many every day appliances. At the magnetic poles the Earth’s magnetic field is approximately 0.7 Gauss compared to the Gauss value of a relatively small 10mm diameter x 5mm thick N42 neodymium magnet which can reach 5100 Gauss.

It is this magnetic field that makes a compass point north but for many species, the Earth’s magnetic field has a much more profound role…

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Heat-assisted magnetic recording – A new approach for data storage

hard disk drive

Ordinarily, heat and electronics aren’t the best of companions; even less unsuited partners are heat and some magnetic materials!

However, a new technology being developed by Seagate for the next generation of storage devices, known as ‘heat-assisted magnetic recording’ is breaking the convention. The technology is heralded as revolutionary and could significantly increase the amount of data that can be stored on a hard drive by increasing storage density.

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Magnetism teaching resources

Magnetism for kids title

The Internet is full of useful information, including thousands of fabulous teaching resources created for every subject by teachers, schools and organisations. At first4magnets.com we are passionate about providing great, useful information about magnets for people young and old. Take a look at these free teaching resources we’ve put together. Please feel free to use and share :)

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Will a magnet damage my smartphone?

A broken smartphone with a smashed screen.

Since the days of the first personal computer it has been part of ‘geeklore’ (like folklore but more interesting) that magnets are bad for all things electronic. But come on I hear you say, we’ve moved on from the days of the faithful floppy disk and the cumbersome CRT monitor, surely this can’t be the case? Magnets can’t seriously damage my iPhone, can they?

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