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Is there a metal which on conducting a small amount of electricity becomes a magnet?
Answer 1:

I did some research online and could not find anything that becomes a magnet when it conducts electricity. This doesn’t necessarily mean a special material like that does not exist, but I think it makes sense that a material that becomes a magnet upon conduction would be hard to make.

Here’s why:

There are two types of magnetism: intrinsic magnetism which is caused by the “spin” of electrons and induced magnetism which is caused by the motion of electrons. (Electrons don’t actually physically spin. Spin is just a fundamental property of electrons from quantum mechanics, like the way charge or mass are properties. Physicists called the property “spin” because the way spin factors in to electron interaction is kind of like how the angular momentum of rotating objects interacts. For this explanation all you need to understand is the spin gives electrons, among other things, a fundamental magnetic moment)

The magnets one typically thinks of when they imagine magnets are a set of magnetic materials called ferromagnets. These are a special class of materials that retain magnetic moment even when there is no external magnetic field, and they do this through intrinsic magnetism. In quantum mechanics electrons can either have a “spin up” or a “spin down” and when an up and down electron are paired together, their magnetic properties cancel out. Normally electrons like to pair up, but in some materials one or some of the electrons are left without a mate. This net imbalance of ups and downs can create a magnetic field, and in the case of a ferroelectric material, all of the magnetic grains created by this imbalance want to lie parallel and stay parallel when a magnetic field is applied. Because the grains want to stay pointed the same direction, a ferromagnet remains magnetic in the absence of a field

. However, you can also create magnets though the movement of electrons (i.e. current). These are called electromagnets. When current runs through a wire, it creates rings of magnetic field. When you loop a wire many times around a metal, all of the little magnetic fields from the loops of wire line up and induce a larger field in the central metal. You can actually make an electromagnet at home with a few supplies.

Check out how in this video! click here to watch The important thing to understand here, though, is that the metal that becomes the electromagnet isn’t actually conducting any electricity, only the wire around it is.

The reason it would be hard to make a material that turns into a ferromagnet upon conducting a small amount of current is that you would have to find some way to have current affect the direction the magnetic grains are pointing (or possibly have current activate the grains?) and as far as I know, the two are not normally coupled that way. But perhaps you will find a way to connect them in the future!


Answer 2:

Any metal will generate a magnetic field if you flow current through it. You can determine the magnetic field by the "right hand rule," by pointing your right thumb in the direction of current flow. The direction of the magnetic field is given by the orientation of your curved right fingers. Strictly speaking, an object generating a magnetic field is a magnet, so this means that as long as current is flowing, your metal is a magnet.



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