なぜ回る？不思議なモータ／Why Does It Spin? A Mysterious Motor
49 هزار بار بازدید -
3 سال پیش
-
DENJIRO: Look at what I’ve
DENJIRO: Look at what I’ve made today.
GIRL: It’s so cute!
DENJIRO: This merry-go-round runs on an interesting mechanism. On the top are lots of coils. When I lift the coils, you can see that there’s a copper plate. When I put the coils back and turn the switch on... it starts to spin. However, the coils and copper plate aren’t touching each other.
GIRL: So how is it spinning?
DENJIRO: The keyword here is: rotating magnetic field. I have here a potter’s wheel with magnets on it. I’m going to put a board on it and sprinkle iron sand over it. You can see the magnetic field lines. Now I’m going to spin the magnets underneath.
GIRL: The iron sand is spinning!
DENJIRO: This is a rotating magnetic field. Next, I’m going to place a disc with one-yen coins on top of the magnets. One-yen coins don’t stick to a magnet. Now what will happen when I spin the magnets underneath?
GIRL: The one-yen coins are spinning too!
DENJIRO: Even with a metal that doesn’t stick to a magnet, if you spin a magnet close by, you can move it through a rotating magnetic field. For the merry-go-round we saw earlier, I had electricity run through opposing coils in a circular motion and made them into electromagnets. A copper plate doesn’t stick to a magnet, but it spun due to the rotating magnetic field. This kind of motor is called an “induction motor.”
NARRATOR: The induction motor was invented by Nikola Tesla, an electrical engineer who worked in the United States. In recent years, induction motors have evolved greatly, and they are used in electric cars as well.
DENJIRO: I hope energy will bring you all happiness. Our magic word is "Happy Energy!"
GIRL: It’s so cute!
DENJIRO: This merry-go-round runs on an interesting mechanism. On the top are lots of coils. When I lift the coils, you can see that there’s a copper plate. When I put the coils back and turn the switch on... it starts to spin. However, the coils and copper plate aren’t touching each other.
GIRL: So how is it spinning?
DENJIRO: The keyword here is: rotating magnetic field. I have here a potter’s wheel with magnets on it. I’m going to put a board on it and sprinkle iron sand over it. You can see the magnetic field lines. Now I’m going to spin the magnets underneath.
GIRL: The iron sand is spinning!
DENJIRO: This is a rotating magnetic field. Next, I’m going to place a disc with one-yen coins on top of the magnets. One-yen coins don’t stick to a magnet. Now what will happen when I spin the magnets underneath?
GIRL: The one-yen coins are spinning too!
DENJIRO: Even with a metal that doesn’t stick to a magnet, if you spin a magnet close by, you can move it through a rotating magnetic field. For the merry-go-round we saw earlier, I had electricity run through opposing coils in a circular motion and made them into electromagnets. A copper plate doesn’t stick to a magnet, but it spun due to the rotating magnetic field. This kind of motor is called an “induction motor.”
NARRATOR: The induction motor was invented by Nikola Tesla, an electrical engineer who worked in the United States. In recent years, induction motors have evolved greatly, and they are used in electric cars as well.
DENJIRO: I hope energy will bring you all happiness. Our magic word is "Happy Energy!"
3 سال پیش
در تاریخ 1400/03/07 منتشر شده
است.
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