Why are magnets magnetic?

[kirkster501]

They are fascinating things - I bought one for my 6 year old daughter. Daddy why are they magnetic? Well sort of answered about electrons being aligned in one direction by the electromagnetic field etc etc. But is that the right answer? And why? Why should some metals exhibit this and not others - aluminium for instance?

[Stargazer33]

It's magic!

[ronin]

Not electrons, I'm afraid. Idea is "similar" in a way.

The idea is that you consider they are made up of many (infinite?) small magnetic cells and that for a material in the non-magnetic state they are randomly arranged. So in effect the Norths and Souths cancel out

When you magnetise them all these little magnetic cells orientate themselves the same way and so reinforce themselves.

In a magnetic material when you remove the field that aligned them they stay orientated the same and so the material now has a North and South magnetic pole. Otherwise they all return to random and the Norths and Souts cancel out and the material is no longer magnetic. (Not sure this may be termed paramagnetic).

Have to say nice explanation but never seemed adaquate.

Called the domain theory of magnetism.

Put forward by a Dr Weisz (that is something I will never forget!!! )

I assume that in a material like Aluminium the cells can never be reorientated whether they are in a magnetic/electric field or not, so never demonstrate magnetism. That raises the question are there any megnetic cells/domains present at all.

[Macavity]

The fundamental origin is with electron spin in the atoms:

http://en.wikipedia....ism#Explanation

Better than me trying to remember this sort of stuff?

[ollypenrice]

The best kind of questions are the ones like, Why are magnets magnetic? Wonderful question. Silly questions are ones which people dare to ask. Give me the ones they don't usually dare to ask any day.

Olly

[Qualia]

Silly questions are ones which people dare to ask. Give me the ones they don't usually dare to ask any day.

That's lovely, Olly. I like that sentiment a lot

I'm sorry for 'derailing' the thread, but I'm having a period of 'silly' questions that I've been toying with recently. They don't have a lot to do with science or astronomy but I thought it would be nice to share a couple of them...

Is freewill the cunning liberty of determination?

What is the relationship and distinction between reality, illusion and that which resembles or counterfeits reality?

What is the being of a sandcastle?

Why isn't there relatively speaking so much blue food in existence?

[Demonperformer]

"Why are magnets magnetic?"

Otherwise they would just be ordinary lumps of metal

I'll leave my name in the wastepaper bin as I go ...

[ShaunyC]

Magnetic materials = arangment of magnetic fields in the atoms

Electro magnets = special relativity

How to destroy a magnet = heat

[ScottS]

I thought magnets exist so our kids can construct meaningless sentences on the fridge.

[cosmiquery]

Rare earth magnets are the best.

[gkec]

I always liked "Why are lorries?"