DENJIRO: Today, I have an experiment that deals with the mechanism of a transformer. A transformer is a machine that increases or decreases voltage. You can find them on utility poles. Here, I have a coil that has 250 turns. I’m going to place this in a metal ring.
NARRATOR: The coil and metal ring are not directly connected to each other.
DENJIRO: I will attach the coil to a power source of 100 volts. I have here another coil with 250 turns. I will connect an incandescent light bulb to the coil and place it in the metal ring. Now, I will turn on the AC power source.
GIRL: The light bulb turned on!
DENJIRO: The two coils are not directly connected to each other, but the light bulb turned on. Why is that? When an alternating current is run through the coil, a magnetic force is produced in the metal ring. Due to this magnetic force, electricity is produced in the other coil, and so the light bulb turned on.
Actually, we can use this mechanism to change the voltage by changing the number of turns on the coil. That’s what a transformer is. Of the two coils, I’m going to change one to a coil with a different number of turns. The new coil has 25,000 turns. By making the number of turns 100 times bigger, the voltage will become 100 times greater. The 100V AC power source is connected to the coil with 250 turns. The coil with 25,000 turns is connected to this V-shaped electrode. Let me turn the power on.
GIRL: Wow!
DENJIRO: Due to the high voltage of 10,000 volts, which is 100 times 100 volts, there is an electrical discharge between the electrodes. As you can see, you can change the voltage by using two coils with a different number of turns.
NARRATOR: An electrical substation is a facility that adjusts the voltage of electricity sent from a power plant. There’s actually a substation in the basement of Nagoya Castle. In order to reduce power loss during transmission and stably send electricity, high-voltage electricity that comes to the substation is transformed before being sent to homes.
DENJIRO: I hope energy will bring you all happiness. Our magic word is "Happy Energy!"