Stuff You Should Know – Selects: How Magnets Work

Intro

In this week’s episode of “Stuff You Should Know” podcast, the hosts delve into the fascinating world of magnets and how they work. Discover the history of magnets, the different types of magnets, and their applications in everyday life. Join the hosts as they unravel the mysteries of magnetism and its impact on our world.

Main Takeaways

History and Types of Magnets

• Magnets were discovered in Magnesia, Greece.
• There are three types of magnets: permanent, temporary (or soft), and electromagnets.
• Ceramic magnets are the weakest commercially available magnets, while neodymium and samarium magnets are the strongest and incorporate rare earth metals.
• Loadstone is the natural strongest magnet, and its discovery led to further exploration of magnetism.
• Early compasses were made by magnetizing a pin using loadstone.

How Magnets Work

• Magnets have a north and south pole, and opposite poles attract while like poles repel.
• Magnetism is one of the four fundamental forces of the universe, along with gravity and the strong and weak nuclear forces.
• Magnetic domains are part of the physical structure of any ferromagnetic material and are each like their own tiny magnet.
• To make a magnet, you need to get all the magnetic domains flowing in the same direction.
• The strength of a magnet depends on how hard it was to get the magnetic domains to move in the same direction.

Applications and Misconceptions

• Magnets are used in compasses, burglar alarms, electric motors, car speedometers, cassette tapes, old-fashioned cathode-ray tube television sets, and speakers.
• Maglev trains and roller coasters utilize super magnets for propulsion and braking.
• Magnetic resonance imaging (MRI) relies on magnets for medical diagnostics.
• Pulse electromagnetic fields are used by doctors to heal broken bones and may be used by astronauts to maintain bone density.
• Swallowing magnets can be dangerous and may require surgery for removal.

Podcast Recommendations and Fun Facts

• Podcast recommendations: “How Rude Teneridos” and “Hallmark Junkies.”
• Magnets are the spin of electrons and can be measured using a goss meter.
• The magnetosphere is a protective layer around Earth that causes the northern and southern lights.
• Static magnetic therapy, such as magnetic bracelets and insoles, has not been proven to have any benefits.
• Americans spend about $500 million per year on magnetic treatments, while worldwide it is about $5 billion per year.

Summary

History and Types of Magnets

Magnets have a rich history, with their discovery dating back to Magnesia, Greece. There are three main types of magnets: permanent, temporary, and electromagnets. Permanent magnets, such as ceramic magnets, are the weakest commercially available magnets, while neodymium and samarium magnets are the strongest and incorporate rare earth metals. Loadstone, a natural magnet, played a crucial role in early compasses.

How Magnets Work

Magnets have a north and south pole, and their magnetic forces flow in opposite directions when brought together. Magnetism is one of the four fundamental forces of the universe, and magnetic domains within ferromagnetic materials contribute to their magnetic properties. Aligning these domains in the same direction creates a magnet. The strength of a magnet depends on the difficulty of aligning the domains.

Applications and Misconceptions

Magnets find applications in various everyday items, including compasses, burglar alarms, electric motors, car speedometers, cassette tapes, television sets, and speakers. Super magnets are used in maglev trains and roller coasters for propulsion and braking. Magnetic resonance imaging (MRI) relies on magnets for medical diagnostics. Doctors also utilize pulse electromagnetic fields to heal broken bones, and astronauts may use them to maintain bone density. However, swallowing magnets can be dangerous, and static magnetic therapy lacks scientific evidence of benefits.

Podcast Recommendations and Fun Facts

For podcast enthusiasts, “How Rude Teneridos” and “Hallmark Junkies” are highly recommended. Magnets are measured using a goss meter, and the magnetosphere around Earth produces the mesmerizing northern and southern lights. Despite the popularity of magnetic treatments, static magnetic therapy has not been proven effective. Americans alone spend around $500 million per year on magnetic treatments.

Conclusion

Magnets have a fascinating history and play a significant role in our daily lives. Understanding how magnets work and their various applications opens up a world of scientific wonder. From compasses to medical diagnostics, magnets continue to shape our technological advancements. Just remember to handle magnets with caution and be wary of unproven magnetic therapies.