What Is a Horseshoe Magnet?

Your refrigerator door, the motors in the washer and dryer, the front doorbell, and the stereo speakers in the family room all have something in common. They all rely on magnets to function. There are two types of magnets: permanent magnets, like the ones holding your shopping list on the refrigerator door, and electromagnets, like the crane that lifts cars at the junkyard. An electromagnet requires electricity to be magnetic. A permanent magnet does not. A horseshoe magnet is a permanent magnet.

Magnets

Magnetism

Refrigerator magnets

Would it surprise you to learn that magnetism is still something of a mystery? The commonly accepted theory is that permanent magnets have tiny parts, called domains, that are aligned in such a way that the energy from the electrons in those domains creates magnetism. Every magnet has two poles, called North and South. If you try to put two North poles or two South poles together, they will push away from each other, but a North pole and South pole held close will attract each other.

Earth as a Magnet

The Earth has a magnetic field.

The Earth is the biggest magnet around! The center of the Earth, very, very deep inside, is made of liquid metals. When the Earth turns every day, those metals rub together, and the friction creates a magnetic field.

Magnet Materials

Most magnets are made of iron.

Permanent magnets can be made of iron, nickel, or cobalt. These are the only three elements we know of that can be magnetized. Other materials, like wood or rubber, or even other metals like gold or silver, also have domains, but their domains are unaligned, or randomly arranged.

The Aurora

The Earth's poles can create an aurora.

Sometimes the Earth's magnetic field makes particles from space glow. If you live very far north, like in Alaska, or very far south, like in Australia, you may see the sky light up at night with shimmering colors called an aurora. In the north, these lights are called the aurora borealis, which means northern lights. In the south, they are called aurora australis, which means southern lights.

Magnet Shapes and Sizes

This tiny disc can be a strong magnet.

The more mass a magnet has, the stronger it can be. That's what makes the Earth such a powerful magnet. We use magnets shaped like discs, bars, or u-shaped, like a horseshoe. A horseshoe magnet can come in many different sizes, from the size of your little finger to the size of your whole head! The poles on a horseshoe magnet are the two ends of the u-shape. Horseshoe magnets are handy for picking things up, because their shape makes a natural handle.

References

• Magnet Man - Cool Experiments
• High School Magnetism

Resources

• Magnet Man - Cool Experiments