Permanent Magnets: Questions Answered

In summary, we have discussed the most powerful permanent magnets and the ways to make them even stronger. Permanent magnets are based on ferromagnetism and rare Earth magnets, such as neodymium, are the strongest ones available. One way to make a magnet stronger is by placing iron behind it to increase the magnetic flux density. The shape of the magnet also plays a role in its strength. According to the website provided, NdFeB magnets are currently the strongest ones available, with a magnetic flux density of 1 Tesla.
  • #1
korneld
22
0
I have a few questions about permanent magnets:

What are the most powerful permanent magnets made of? How strong do they get?

What are the ways to make an already powerful magnet even stronger?

I understand that placing iron behind it will amplify it. Why?

I also read somewhere that shape is really important as well. What are the best shapes to make a magnet stronger? How does that work?


Thank you.
 
Physics news on Phys.org
  • #2
1. What are the most powerful permanent magnets made of? How strong do they get?
Ans: permanent magnet in fact is base on ferromagnetism. i think u can look it up here http://en.wikipedia.org/wiki/Permanent_magnet#Permanent_magnets
i dun know what is the strongest magnet in the world. but if u want to generate a very strong magnetic field, u can use a superconducting solenoid. Typically i can generate a B-field around 10Tesla.

2. What are the ways to make an already powerful magnet even stronger?
Ans: i think what u are talking about is to put a iron coil inside a solenoid to make a stronger B-field, rite? this is because the iron would confines the magnetic flux so the the magnetic flux density(B-field) increases.

3. What are the best shapes to make a magnet stronger? How does that work?
Ans: i dun know, where did u read about this?

hope it helps^^

kit
 
  • #3
The strongest I know of that are available are rare Earth magnets such as neodymium. I'm sure there are stronger ones (probably rare-earth) that could be made.

Oh, and the strongest magnetic fields ever discovered are in magnetars.
 
Last edited:
  • #4
Thnks for your replies!

Kit:

This is the page where I read about steel increasing flux density and the shape being important: http://www.wondermagnet.com/magfaq.html#q71

Here is the quote:

"B (flux density): This is the measurement (in Gauss or Tesla) you get when you use a gaussmeter at the surface of a magnet. The reading is completely dependant on the distance from the surface, the shape of the magnet, the exact location measured, the thickness of the probe and of the magnet's plating. Steel behind a magnet will increase the measured 'B' significantly. "

It is also common for a magnet to be encased in steel when used in speakers, isn't it?

Also all solutions would have to be at room temperatures (and here on Earth :smile: )

The website referenced above also says that NdFeB (Neodymium-Iron-Boron) magnets are the strongest ones available today (a/ 1T). I was wondering if that was true.
 

What are permanent magnets?

Permanent magnets are objects that produce their own magnetic field, which can attract or repel other magnetic materials. They are made of materials such as iron, cobalt, and nickel, and retain their magnetism even after the external magnetic field is removed.

How are permanent magnets made?

Permanent magnets are made by exposing magnetic materials to a strong magnetic field, either through electromagnetic induction or by rubbing the material against a magnet. This aligns the magnetic domains within the material, creating a permanent magnetic field.

What are the different types of permanent magnets?

The three main types of permanent magnets are ceramic (also known as ferrite), alnico, and rare earth magnets. Ceramic magnets are the most common and inexpensive type, while alnico magnets are more powerful but also more expensive. Rare earth magnets, such as neodymium and samarium cobalt, are the strongest type of permanent magnet available.

What are some common uses for permanent magnets?

Permanent magnets are used in a wide variety of applications, including generators, electric motors, speakers, hard drives, and magnetic levitation trains. They are also commonly used in everyday objects like refrigerator magnets and magnetic toys.

Can permanent magnets lose their magnetism?

Yes, over time permanent magnets can lose some of their magnetism, especially if they are exposed to high temperatures or strong opposing magnetic fields. However, this process is very slow and can take years or even centuries for significant changes to occur.

Similar threads

  • Electromagnetism
Replies
3
Views
1K
Replies
8
Views
2K
Replies
2
Views
502
  • Electromagnetism
Replies
13
Views
1K
  • Electromagnetism
Replies
7
Views
1K
  • Electromagnetism
3
Replies
74
Views
12K
Replies
19
Views
968
Replies
5
Views
1K
  • Electromagnetism
Replies
26
Views
3K
  • Electromagnetism
Replies
2
Views
1K
Back
Top