Open Source Antibiotics Favorites, 28 Dec 2008

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From YouTube: Feynman: Magnets FUN TO IMAGINE 4 But see NEW UPDATED file at https://tinyurl.com/ycphc432

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This is the original upload of the piece. There is now a much higher quality version at https://tinyurl.com/ycphc432 Enjoy!

See also Feynman MAGNETS EXTRA on YouTube http://www.youtube.com/watch?v=IdA-l_Lnp2E

"Water, fire, air and dirt/
F*cking magnets, how do they work?/
And I don't wanna talk to a scientist/
Y'all motherf*ckers lying, and getting me pissed"

- Insane Clown Posse, Miracles (2009)

Here, physicist and Nobel laureate Richard Feynman explains to a non-scientist just how difficult it is to answer certain questions in lay terms! A classic example of Feynman's clarity of thought, powers of explanation and intellectual honesty - and his refusal to 'cheat' with misleading analogies... From the BBC TV series 'Fun to Imagine'(1983). You can now watch higher quality versions of these episodes at the BBC website www.bbc.co.uk/archive/feynman/ Also the 1981 'Horizon' and 'Nova' Feynman documentary THE PLEASURE OF FINDING THINGS OUT

A

If you get hold of two magnets and you push them, you can feel this pushing between them turn it on the other way in it and they slam together. Now what is it the feeling between those two magnets? What.

B

Do you mean what's the feeling to.

A

It is all there and there I mean that the sensation is that there's something there. When you push these two magnets together, listen.

B

To my question, what is the meaning when you say that there's does this a feeling? Of course you feel it.

A

Now, what do you want to know? What I want to know is: what's going on between.

B

These these two bits of metals repel.

A

Each other and well then, what does that? But what does that mean or why are they doing that or how are they doing it.

A

Your ass I must say, I think that's a perfectly reasonable question of.

B

Course, the reason it's an excellent question: okay,.

B

Put the problem that you're asking you see when you ask why something happens, how does a person answer why something happens? For example, aunt Minnie is in hospital. Why? Because she slipped through what out and she slipped on the ice and broke her hip that satisfies it. People it satisfies, but it wouldn't satisfy. Someone who came from another planet knew nothing about things. You first should understand why, when you break your hip, do you go to the hospital?

B

How do you get to the hospital with the went? The hip is broken well because her husband, seeing that she had the hip with book and call the hospital up and send somebody together, all that is understood by people and when you explain it a why you have to be in some framework that you allow something to be true, otherwise, you're perpetually asking why? Why did the husband call up the hospital? Because husband is interested in his wife's welfare?

B

Not always some husbands aren't interested in their wives when they're, drunk and they're angry, and so you begin to get a very interesting understanding of the world and all its complications and all of it. If you try to follow anything up, you go deeper and deeper in various directions. If, for example, you go oh, why did she slip? The ice will lies to Slippery. Everybody knows that no problem, but yes, why is ice? Slippery?

B

That's kind of curious ice is extremely slippery. It's very interesting. You say how does it work you? Couldn't you see? So you could either say I'm satisfied that you've answered me ice is slippery. That explains it or you could go out and say.

B

Why is ice, slippery and then you're involved with something, because there aren't many things as slippery as ice, it's very hard to get greasy stuff, but that's sort of wet too slimy, but a solid, that's so slippery, because it is in the case of ice that when you stand on it they say momentarily. The pressure melts the ice a little bit. So you got a sort of instantaneous water surface on which you're slipping.

B

Why on ice are not on other things, because ice expands when it water expands when it freezes, so the pressure tries to undo the expansion and melts it is capable of melting but other substances, cracked, when they're freezing and when you push them they're, just as satisfied to be solid.

B

Why does water expand when it freezes and other substance don't expand when they freeze all right? I'm, not answering your question but I'm telling you how difficult the? Why question is you have to know what it is that you're permitted to understand and allow to be understood and known and what it is you're, not you'll notice in this example that the more I ask why it gets interesting afterwards.

B

My idea that the deeper a thing is the more interesting in it and we could even go further and say: why did she fall down once you slip that has to do with grabbing involves in all the planets and everything else never mind it goes on and on, and when you ask, for example, why two magnets repel there are many different levels. It depends on you, whether you're, a student of physics or an ordinary person that doesn't know anything or not.

B

If you're somebody who doesn't know anything at all about all I can say, is that there's a magnetic force that makes them repel and that you're feeling that forth? You see, but that's very strange, because I don't feel kind of force like that.

B

In other circumstances, when you turn them the other way, they attract there's a very good knowledge as force electrical force, which is same kind of a question, and you say that's also very weird, but you're not at all disturbed by the fact that when you put your hand on the chair, it pushes you back, but we found out by looking at it.

B

But that's the same force as a matter of fact: the electrical force not a magnetic exactly a night chase, but it's the same electrical repulsion 'z that are involved in keeping your finger away from the chair, because everything's made out of it's electrical forces in minor in microscopic details. There's other forces involved, because this is connected to electrical forces.

B

It turns out that the magnetic and the electric force with which I wish to explain these things, this repulsion in the first place, is what ultimately is the deeper thing that we have to start where we can start with to explain many other things that looked like they were. Everybody would just accept them. You know you can't put your hand through the chair, that's taken for granted, but that you can't put your hand through the chair when looked at more closely, why that involves these same repulsive forces that appear in magnets.

B

The situation you then have to explain is why and magnets it goes over a bigger distance than an ordinarily and there it has to do with the fact that in iron, all the electrons are spinning in the same direction. I will get lined up and they magnify the effect of the force until it's large enough at a distance that you can feel it.

B

But it's a force which is present all the time and very common and is in a basic force of almost I mean I can go a little further back if I were more technical, but at an early level. I have just got that to tell you that's going to be one of the things you'll just have to take as an element in the world. The existence of magnetic repulsion or electrical electrical attraction magnetic attraction.

B

I can't explain that attraction in terms of anything else, that's familiar to you, for example, if we said the magnets attract like as if they were connected by rubber bands, I would be cheating you because they're not connected by rubber bands, I shouldn't be in trouble.

B

You soon asked me about the nature of the band and secondly, if we were curious enough, you ask me why rubber bands tend to pull back together again and I would end up explaining that in terms of electrical forces, which are the very things that I'm trying to use the rubber bands to explain so I have cheated very badly. You see so I'm not going to be able to give you an answer to why magnets attract each other, except to tell you that they do and to tell you that.

B

That's one of the elements in the world of the different kinds of forces there are electrical forces, magnetic forces of gravitational forces and others, and those are some of the parts. If you were a student you'd go fer I could go further. I could tell you that the magnetic forces are related to the electrical forces very intimately that our relationship between the gravity forces and electrical forces remains unknown and so on.

B

But I really can't do a good job, any job of explaining magnetic force in terms of something else that you're more familiar with, because I don't understand it in terms of anything else that you're more familiar with.