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  • I've got a magnet here.

  • Big circular magnet.

  • It's a ring shaped magnet, rather like facilitate.

  • So it goes around.

  • This is a tiny little compass needle, so this seems to be pointing upwards.

  • It moves across, it goes horizontal, and then it goes downwards out the other side.

  • There's a magnetic field coming out.

  • I've got another little magnet.

  • This is again a ring magnet on the top.

  • You can see the magnetic field is pointing outputs on on the bottom.

  • It's going the other way.

  • So now if I bring this downwards, there's a repulsion and you will feel as you bring it down.

  • There's a repulsion between these two.

  • It's a so I have here really big magnet.

  • When I want to do is place his big magnet over the center, and if I get it over the center, you can see will start to float because of the repulsion between this magnetic pole on the magnetic pole in the base.

  • So as I lift this up, it will slide down.

  • He wants to stay about that height.

  • This is a really strong magnet, so it's probably two inches or more above.

  • So now what I want to do is get this to be floating above there.

  • And I can't do that normally because it wants to turn that way.

  • So I try and get it to go there and it will fall down.

  • So the trick is to spin it, because if you spin it, it has a persistence.

  • It wants to stay upright like a little spinning top.

  • So the object is to take this thing and put it in a space above their spinning round so it doesn't fall down and you do that in two steps.

  • The first step is to spin from here.

  • You see how it wants to repel against.

  • And of course, I can go for half an adult this take 57 572 until I get one that works on.

  • Then I lifted up bit by bit to the point where is just comes up on.

  • Then it starts to float in the air.

  • And if I got this level, it will stay there for a nice length of time.

  • This is not held up.

  • I should have balanced it a bit better on its smallest level.

  • There.

  • Art and pass a ring through it.

  • either direction.

  • Nothing is supporting you.

  • Oh, magic is involved.

  • No animals were killed on there.

  • It floats for about a minute and 1/2 and I don't know what to say.

  • That will keep you amused for that length of time.

  • It starts to process when it slows down.

  • Because of the friction of the air, the rotation rate goes down a little bit.

  • So here it's spinning around.

  • Maybe 25 rotations per second on it slows down, it slows down bit by bit, and you can feel after world as it slows down, the direction is pointing starts to wiggle around a little bit.

  • And then about 10 seconds after that, it plummets down to the ground.

  • Well, that this is the place where we find out whether this is all a dream or not.

  • It's just waggling so much that I'm sure.

  • Yes, there it is.

  • Yeah, it's a mixture of repulsion and gyroscopic motion.

  • But the paper that came out to explain Dawood Bhai Sir Michael Berry, who is one of the leading theoretical physicist, his generation and he loves all these toys.

  • He would go and analyze him in gory detail.

  • The idea of having a magnet.

  • A rotating bag?

  • Well, no spinning magnet has analogies with protons and neutrons, which will be in traps or atomic particles, which could be in magnetic traps.

  • So it is used, but not quite in this toy like form.

  • I just I have found I'm addicted to this.

I've got a magnet here.

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B1 中級

旋轉磁鐵 - 60個符號 (Spinning Magnet - Sixty Symbols)

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    林宜悉 發佈於 2021 年 01 月 14 日
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