How Do Electric Generators Work?

Video Transcript

"Hi, I'm Steve Jones and I'm going to explain how an electrical generator works. Well, in the generator I need certain things. First of all, I need what we call field magnets. The reason for these is that I need a magnetic field in the first place. So these are field magnets. And here we've got a field going from north to south. Inside that field I've got a coil of wire. This is it from the top, there's the coil of wire and this goes around and around, but I've just shown one. And this is looking at it from the side. Now as you can see, we've got a field line going across. This you can't see of course, this is just representing the field. And the fact is that when this wire, let's say this wire, actually this will be going down. When this wire goes through these field lines, in this wire you will get an electrical current. So as it goes down it generators an electric current in this coil of wire, and that electric current comes through this so that we get an electrical output. So whenever this wire cuts through this magnetic field it generates an electric current. Now if you've got many, many coils on here, it generates this current for each of the coils. And therefore you get a bigger current. Now this will go around and around and around. And the electrical output actually will not be a steady one, it won't be a steady five volts, it won't look like this. It won't look like that. It will actually look something like this where it goes positive and negative from zero. So sometimes it goes forward, sometimes it goes backwards, it's called alternating current. Alternating current. So this alternating current which is what you have in your home, and what you get from the mains, is what you will get from a generator of this kind. Here we have what is called slipperings which connect the coil to the output. So this briefly, very briefly, is how an electrical generator works."