Dr Vetrovec intends to perform his version of the trick at atmospheric pressure, and using permanent magnets.

维特威克博士想要在大气压力下使用永来实现他的这种把戏。

Cerium is also used in permanent magnets for obvious applications in magnetism.

铈也用于永，在学领域有明应用。

A larger ring, called a rotor, contains permanent magnets and rotates around the stator.

一个较大的环，称为转子，内含永，并围绕定子旋转。

So why is it that permanent magnets do not do this?

那么为什么永不会这样做呢？

This makes electromagnets quite different from permanent magnets.

这使得永有很大不同。

So let's take a look at that and compare permanent magnets to electromagnets.

让我们看一下并将永进行比较。

So now what you have created is a permanent magnet.

所以你现在创造的是一个永。

This is different from a permanent magnet because permanent magnets don't need this wire.

这永不同，因为永不需要这种线。

And it will make a permanent magnet.

并且它会成为一个永。

And so what is a permanent magnet?

什么是永？

Permanent magnets also have fixed poles.

永也有固定极。

Do we have a permanent electrostatic magnet?

我们有永久的静铁吗？

On the other hand, permanent magnets are always on.

另一方面，永始终处于开启状态。

As we increase the magnetic field it quickly, all of these dipoles align, the domains align and we have a permanent magnet.

当我们迅速增强场时，所有的矩都会对齐， 畴也会对齐， 从而形成永。

They are used in super permanent magnets and therefore on that absolutely critical instrument of economic warfare, which is called the vacuum cleaner.

它们被用于超强永， 因此成为经济战中一个绝对关键的工具，也就是吸尘器。

And so if I were to change this and make it a permanent magnet, watch what happens to those domains.

所以如果我把这个变成永，看看这些畴会发生什么变化。

But if I were to take paper clips for example, put them next to a permanent magnet the could be an induced magnet.

但是以回形针为例，如果把它们放在永旁边， 它们就可能会变成感应。

Permanent magnets have a fixed strength, but we just talked about how we can change the strength of electromagnets, so electromagnets have adjustable strength.

永的强度是固定的，但是我们刚才讲了如何改变铁的强度，所以铁的强度是可调的。

If you heat up a permanent magnet above what is called the curie temperature, all those magnetic fields get scrambled and it is not a magnet anymore.

如果你将永加热到所谓的居里温度以上，所有的场就会变得混乱， 它就不再是铁了。

Permanent magnets do not need a power source, but this means that we can also turn electromagnets on and off, which is pretty cool when you think about it.

永不需要源，但这意味着我们也可以打开和关闭，想想看，这真是太酷了。