How Do Magnets Work? What They’re Made Of and Why They Stick Around

Promo Expert

Published: September 10th, 2020

They're all over your refrigerator, but how much do you really know about magnets? Sure, you might have had a science teacher who did an experiment with them in 3rd grade, but you're an adult and it's time for a refresher!

Stick right here and let's get into all you need to know about magnets. You'll find out why they stick, what they're made of, and whether or not they work in outer space.

What Are Magnets?

Magnets are objects that produce an invisible moving electric charge known as a magnetic field. These objects can stand on their own, such as refrigerator magnets, or be part of another item, such as the magnets found inside of your cell phone.

When you think of the word "magnetism," you should also think of the word "attraction." Magnetic objects can't resist the pull of other magnetic objects that contain the opposite pole. It's a natural reaction – kind of like the attraction you feel toward certain movie stars.

What is a Magnetic Field?

A magnetic field is an area of force that is created by a magnetic object or particle. This forcefield is completely naked to the eye, but insanely powerful.

The measurement of a magnetic field's force is referred to as the Lorentz Force Law. Basically, the density of the lines from the north-seeking to the south-seeking poles indicate the power of the field. The closer to the poles, the stronger the pull. The farther away, the weaker.

Some magnets have a more powerful magnetic field than others. It just depends on how they're built.

Magnets were first discovered in 1845 in the form of magnetite stones. These are naturally created as the result of volcanic activity.

What Are Magnets Made Of?

Magnets are usually made from iron, but that's not always the case. A magnet can be made of any metal or alloy that contains unpaired electrons, which in chemistry, is when an electron occupies an atom orbit on its own and doesn't have another electron alongside it.

Did you not pay attention in science class? Here's a crash course on how electrons and atoms work!

An atom, like the one pictured above, is a unit of ordinary matter that is part of basically everything. Notice how the electron is on an orbit around the atom. In order for a metal object to be considered magnetic, it must have atoms that only have one electron in an orbit.

What Are the Different Types of Magnets?

As mentioned, magnets can be made of different materials other than just iron. Based on how it's made, a magnet will fall under one of these types:

Alnico
Ceramic
Neodymium
Samarium Cobalt

Alnico

An alnico magnet is any magnet that's made from aluminum, nickel, or cobalt. They're stronger than your typical refrigerator magnet, but still not strong enough to lift a car.

Ceramic

Ceramic magnets aren't particularly strong and usually contain some kind of ceramic material. The magnets on your refrigerator would be an example of this type of magnet.

Neodymium

This type of magnet is made from iron, boron, or a rare-element called neodymium. These are the strongest commercially made magnets on the planet and are used for hard drives, motors, and even dentures!

Samarium Cobalt

A magnet made from samarium and cobalt is insanely strong. This type of magnet is a must-have for serious technology, such as the kind used by the military and NASA!

How Do Magnets Work?

A magnet emits a super strong attractive power known as a magnetic field. As a result, two objects with opposite lines of force, or poles, will naturally be drawn together.

Here's how it works!

Basically, what happens is the electricity in a metal object (the electrons) start moving. As they move, they are drawn toward the south pole, which exists inside of an object made from magnetic metals like iron, nickel, cobalt, steel, or boron.

It's just like Isaac Newton's discovery of gravity. Magnetism isn't something that was invented, it's just something that exists in the universe. You can't stop principles like gravity and magnetism even if you tried!

William Gilbert, the man who discovered magnetism in 1600, is also credited with the invention of the word "electricity."

What Do Magnets Attract?

There are certain metals that are naturally attracted to magnets. These include:

Iron
Nickel
Cobalt
Steel
Boron

Not all metals are magnetic and that's due to how they're made. For instance, gold, silver, and copper repel magnets rather than attract them.

It's the same reason why your refrigerator might not be magnetic. Magnets only work on refrigerators made from magnet attracting metals (iron, nickel, cobalt, steel, or boron). If your fridge is made from aluminum or plastic, a magnet will likely not stick to it.

Why Do Magnets Exist?

Now that you have a good understanding of how magnets work, let’s dive into the various ways they’re used.

What is a Magnet Used For?

You’ll find magnets inside of a variety of objects that you use every day, from televisions and cell phones to speakers and even medical equipment!

Magnets are used for any of the following:

Refrigerators
Microwaves
Dishwashers
Medical Equipment
Electric Cars
Phones
Compasses
Credit Cards
Doors & Doorbells
Televisions
Computers & Tablets
Speakers
Headphones
Fishing
Earth’s Rotation

Refrigerators

Magnets add personality to your fridge. They also hold onto those coupons, grocery lists, and your kid’s report cards and artwork.

Microwaves

You can reheat those leftovers thanks to the power of magnets! The magnets are in vacuum tubes that provide the force necessary for your microwave to work.

Dishwashers

TIf it weren’t for magnets, you’d be washing all those pots and pans by hand! The magnet inside your dishwasher is time activated to run the water and stop it when the cycle is complete.

Medical Equipment

An MRI (Magnetic Resonance Imaging) relies on a strong magnetic field to create detailed images of various parts of the human body. These are used by medical professionals to create a proper diagnosis for their patients.

Electric Cars

An electric car, like a Tesla or Nissan Leaf, contains a coil of wire that is encircled by magnets. The magnetic field that is emitted is what helps give the car its power.

Phones

Certain functions in your cell phone, like the ringtone or the screen, may use magnets. The same can be said for landline phones, which send out electrical currents when a call is being made.

Compasses

The needle inside of a compass reacts to nearby magnetic fields. In doing so, it’s able to give you the right direction to travel.

Credit Cards

Can you picture that stripe on the back of your credit card? That’s actually a magnetic field called a magstripe that interacts with the reader as you make a purchase.

Doors & Doorbells

Many businesses use doors that contain magnetic locks. These stop the door from easily opening and are most ideal for security. Doorbells also use magnets to make that classic ding dong chime!

Televisions

A tube inside of your TV, known as the cathode ray tube, contains a magnet. The image of your favorite show is produced as a bunch of electrons travel on the side of the tube.

Computers & Tablets

Like televisions, computers and tablets also contain cathode ray tubes. Electromagnets bend the flow of the electrons, which make them visible on your monitor.

Speakers

Sound comes from your speakers thanks to electromagnets. Now go pump up the jams, listen to that podcast, or fall down a YouTube rabbit hole.

Headphones

Headphones are basically two speakers on your ears. They work with the same electromagnets that produce sound in regular stationary speakers.

Fishing

Magnet fishing is an activity where people search for metal objects in lakes, rivers, and ponds by tying a strong magnet to the end of their line. The goal is to retrieve items that are lost at the bottom of the water.

Earth’s Rotation

Yes, the planet you live on is a magnet. Scientists think the outer core generates electric currents known as a geomagnetic field. This creates invisible lines of force between the Earth’s poles.

Magnetars are considered the world’s strongest magnets. These are stars that have died off and had a supernova explosion. They’re strong enough to destroy small planets if they get close enough.

How Are Magnets Classified?

Magnets are not just magnets. They’re actually classified in different ways depending on how they’re made. These classifications include:

#1: Temporary
#2: Permanent
#3: Natural

The handy chart below breaks down each classification:

The main difference between a temporary and permanent magnet is that a temporary magnet relies on some other force to work. For instance, electromagnets are temporary because they need electricity. A permanent magnet, on the other hand, retains its magnetism indefinitely.

Both permanent and temporary magnets are created by human hands, while a natural magnet is something that just exists. Think about Earth’s magnetic pull. This would be considered a natural magnet.

You will find that magnets are also classified based on:

Ferromagnetism
Any magnet that retains its properties even if the magnetic field is removed.

Ferrimagnetism
This kind of magnet is characterized by unequal magnetism, which is polarized in opposite directions.

Paramagnetism
Materials, like aluminum or platinum, that are magnetized due to being part of a magnetic field.

Diamagnetism
Materials, like plastic or paper, that are not affected by a magnetic field.

Ferro and ferri magnets are usually considered a type of permanent magnet, while paramagnets are temporary. It helps to know these types, especially if you need a magnet for your next project.

You shouldn’t keep magnets too close to your credit cards or to your electronics like televisions, cell phones, or computers. The magnet could cause unfixable damage.

Does Temperature Affect Magnets?

The temperature could very well affect how well a magnet works. Interestingly enough, heat lowers the magnetism of an object, while cooler temperatures make it stronger.

Let’s say you’re planning a construction project that requires an electromagnetic crane. It’s better to schedule that for the summer than the winter. Not only is this better for the magnet, but your employees will also appreciate the fact that they don’t have to freeze outside.

Would a Magnet Work in Space?

Scientists have determined that magnets would work in outer space. That’s because they don’t rely on gravity or a particular environment in order to function.

As we explore more of our universe, who knows what we’ll discover? Maybe there are aliens out there who are sticking magnets to their own refrigerators!

Stats for Success

As of 2013, about 87% of Americans have magnets on their refrigerators.

The magnets used in MRI machines are 60,000 times stronger than the Earth’s fields.

Junkyard magnets, the ones that lift cars, are as powerful as 2 tesla, which is a unit of measurement for magnetism.

The Bottom Line

Magnetism is a fascinating process that’s worth learning more about. It’s used for everything, from improving our health to helping us explore other planets. So go ahead – give the magnet on your fridge a high five!

Alyssa Mertes

amertes@qualitylogoproducts.com

866-312-5646 x 277

Alyssa is the Lead Copywriter at Quality Logo Products. As a promo expert, she's uncovered the world's first custom tote bag, interviewed the guy behind rock band ACDC's logo, and had a piece published by the Advertising Specialty Institute, a leader in the promotional products industry.

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