permanent magnets Definition and 62 Threads

So we can think permanent magnets to be composed of large number of tiny magnetic dipoles? You can hear this in very elementary introductions. I would guess this is some kind of approximation to the spins of the atoms, or something... There is energy stored in the magnetic field, so if these...

Does a permanent magnet ever loose it's energy or decrease over time? I read somewhere that a "fixed" magnet's energy will dissipate in time as it does work. I don't know what they mean by fixed. Also, will a permanent magnet work without the Earth's energy (eg. in space).

Hello! I have a deeply magnetizing question. I have an attractive magnetic assembly and I am interested in finding some forces, acting on its parts. Set-up details ( if to be specific ): I have two cylinder-shaped neo magnets with identical dimensions and properties, such as residual...

Hi all, i saw many times while browsing that persons like howard johnson, tom beardson, paul monus, etc., are informing themselves that they have invented motors that run only based on the stored energy of the permanent magnets... are they really having that machines..? if yes, i...

I was surprise to find that even HowStuffWorks.com didn't have an article for 'permanaent magnets'. I was wondering, do permanent magnets always have magnetic fields aroung them? What makes them permanent?

Hi all, In one of the books I'm reading, it says that shields are only used in the presence of alternating fields. However, in some websites, I see people using magnetic shields for permanent magnets which has a magnetostatic field. I ran some simulations, and the filed of a permanent magnet...

Hi all, I have this simple question that I never really understood. A permanent magnet generates a magnetic field around itself. Is there an electromagnetic wave propagation associated with this permanent magnet? If so, what is the frequency of the wave? Thanks, Mike

Is it possible to produce electricity by using permanent magnets with no moving parts? I believe that is possible. Because AC current produced by moving armature or copper wire or some other metal in magnetic field. Then without moving wire it should produce DC or some kind of electron flow...

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...

I am posting this here because I have not been able to find the answer anywhere else. I know some of you might find this quite dumb of me, since I have seen some quite learned scholars in this forum, and my question is pretty basic. I am aware I might not be in the right forum. My...

DO NOT TRY THIS EXCEPT ON A JUNK TV OR MONITOR If you hold a strong permanent magnet up to a T.V. screen while it is on, the magnetic field does some really intriguing warping of the image. When you take the magnet away the image goes back to normal except that the color is now patchy and in-...

My physics teacher gave the class a brief explanation of a permanent magnet. If I understood him correctly he basically said the special condition with a permanent magnet is that all the electrons are circling uniformly (in same direction). The poles of the magnet are based on the direction the...