Daming Military Empire

Chapter 228 Demonstration of Electromagnetic Coexistence

What Zhu Cijiong wants Xu Fuyuan and Xia Yunyi to learn is the law of electromagnetic induction. After they have a preliminary understanding of electricity, the magnetism will naturally be demonstrated. The next small experiment he will conduct is to demonstrate the magnetic field lines with iron powder.

At this time, Xu Fuyuan and Xia Yunyi's hearts were already shocked beyond belief, they already vaguely understood that what the emperor asked them to do might have something to do with the thunder and lightning, it was the thunder and lightning above the nine heavens, even thinking about it makes one's heart tremble.

They trembled but Zhu Cijiong didn't tremble. He calmly directed a group of eunuchs to continue the experimental course. Then he brought up a thick square wooden board, which was two feet square and probably about two inches thick. It was square, smooth and flat. It's a fine piece of wood.

Although the board is good, it is not the point. The point is that there are two rectangular grooves cut out on the board, about two fingers thick and thin, about an inch apart.
The answer was soon revealed, and two more eunuchs came up each holding a delicate wooden plate. On the wooden plate were two long black stones, judging by the size, they fit into the grooves of the wooden plate.

Zhu Cijiong picked up a black stone with one hand, and slowly approached it with the back two hands. There was a soft 'pop', and the two stones stuck together. He asked full of hope, "Do you know what this is?"

It's not a novel thing, it's just two magnets. Xu Fuyuan and Xia Yunyi have seen each other before, they looked at me and I looked at you, but they were too embarrassed to answer. He nodded and said: "If you go back to the emperor, we know that this is a magnet."

Now that he knew it, there was no need to bother to explain it. Zhu Cijiong broke apart the two magnets, stuffed them into the grooves of the wooden board, and gestured to Cao Huachun.

Cao Huachun gave a soft order, and immediately two more eunuchs came up with a delicate wooden tray, but this time the things that came up were a bit strange, it turned out to be a stack of thick cardboard with a clean white surface and a box filled with black powder. glass bottle, what is this for?
Zhu Cijiong didn't let them guess. As soon as the things came up, he immediately took a piece of cardboard and put it on the table, then picked up the glass bottle, sprinkled the powder inside evenly on the cardboard, and explained as he sprinkled it: "This It is filled with iron powder, you can look carefully next time."

After he sprinkled the iron powder, he immediately covered the cardboard on the wooden board, the size was just right, the cardboard and the wooden board fit together tightly, like a whole, of course this is not the point, the next is the key point.

Zhu Cijiong flicked the cardboard lightly with his fingers, and a miraculous scene appeared. The iron powder on the cardboard slowly began to form a regular pattern. The place where the magnet was located below was two dense black squares. But it presents evenly spaced arcs, and the arcs in the middle of the two magnets also blend together to form complete circular arcs.

Xu Fuyuan and Xia Yunyi looked at all this in amazement, it's amazing, what's going on?

Zhu Cijiong continued to explain: "A magnet is also called a magnet. There are magnetic lines of force that are invisible to the naked eye around the magnet. These lines of force are inherent in the magnet itself. You don't need to understand how it came about. You just need to know that there is this thing. Come to Fuzhai first. try."

After finishing speaking, he gently picked up the cardboard and put it aside, then picked up the glass bottle on the table and stuffed it into Xu Fuyuan's hand.

Xu Fuyuan was still very interested in this novel 'experiment'. Now that the emperor told him to do it, he didn't hesitate, and took the glass bottle respectfully. Following Zhu Cijiong's example, he took a piece of clean cardboard and put the iron on it. Sprinkle the powder evenly on the cardboard, then cover the cardboard on the wooden board, and gently bounce it up with your fingers.

The iron fans slowly gathered, forming a pattern similar to the one just now, Zhu Cijiong nodded and said: "Well, yes, I read it very carefully, and I learned it very similarly. Fuzhai, you stand back first."

Xu Fuyuan got the emperor's praise, stood back up and down, his nervous mood was relieved.

Next, Zhu Cijiong gently put aside the cardboard that Xu Fuyuan had used, then pulled out a magnet, put it back in the opposite direction, and then said to Xia Yunyi: "Yizhong, you can try it too."

Xia Yunyi has long been eager to try it. Hearing this, he immediately stepped forward to take a piece of clean cardboard. Like Zhu Cijiong, he picked up a glass bottle and sprinkled iron powder evenly on the cardboard, and then covered the cardboard on the wooden board. Bounce gently with your fingers.

The pattern formed this time is different from the previous two. The arcs where the two magnets intersect are actually staggered. Did I do something wrong?Xia Yunyi stared at the magnetic field lines on the cardboard with puffy eyes, and was stunned.

Zhu Cijiong approached kindly, picked up the cardboard and put it aside, then pulled out the two magnets inside, stuffed them into Xia Yunyi's hands, and explained with a smile: "Yizhong, you didn't do anything wrong, this magnet There are polarities, like poles repel, opposite poles attract, just try it out.”

Xia Yunyi heaved a sigh of relief when he heard the words, he was really startled just now, it is not a joke to do something wrong in front of the emperor, at least he would fall out of favor, at worst he would lose his head, luckily he did not do anything wrong.

He settled down, and slowly approached the two magnets in his hands. Sure enough, he felt a force repelling each other. He followed Zhu Cijiong's example again, turned the magnets upside down, and then slowly approached, with a "pop" With a soft sound, the two magnets stuck together.

In the Ming Dynasty, seeing a single magnet was considered knowledgeable, who would be bored to find two magnets to face each other? For a while, Xia Yunyi felt the novelty, and kept turning around while holding the two magnets. , various directions, various angles, approaching again and again, having a great time playing, and staring at Xu Fuyuan on the side.

Seeing this, Zhu Cijiong couldn't help but shook his head and smiled, "Okay, the Ministry of Industry has collected a lot of these things. Later, you can ask Chang Geng for a few dollars to play with. Yizhong, you put the magnet back, and we will continue with the next experiment."

Hearing this, Xia Yunyi blushed with embarrassment, quickly put the two magnets back into the wooden slot, and then stepped aside respectfully.

Zhu Cijiong signaled to Cao Huachun again, and then two more eunuchs came in, but this time the thing for the experiment was a bit big, and they came in with a big wooden plate.

How to describe the thing lifted up this time, simply put, it is a thick wooden board and a wheel for hand spinning.There are also two slots on the plank, but the ones placed inside are obviously not magnets, but ordinary iron blocks; the wheel used for hand spinning is not complete, only the middle round wooden pole, no spinning wheel, and wooden There is also a magnet attached to the rod.

After the two eunuchs put the things on the long table, they retreated respectfully. Zhu Cijiong stepped forward to operate it himself. He first took out two iron bars and demonstrated it to Xu Fuyuan and Xia Yunyi. There was no sign of mutual attraction, and then he said, "This is an ordinary piece of iron, not a magnet. Fuzhai, try it."

After finishing speaking, he stuffed the two iron pieces into Xu Fuyuan's hands. Xu Fuyuan took the two iron pieces and tested them for a few times. As expected, they were two ordinary iron pieces with no magnetism at all. After the test, he respectfully put the iron pieces away Return it to Zhu Cijiong.

Zhu Cijiong took the iron blocks, stuffed them back into the wooden trough, then took a clean piece of cardboard, sprinkled some iron powder evenly, then covered the cardboard on the wooden board, and flicked it up gently with his fingers. Of course, his iron fans didn't move at all.

Zhu Cijiong didn't stop there, but put the cardboard aside, took out another iron block, then picked up a long thin gold wire in the wooden plate, carefully wound it around the iron block several times, and put it on the iron block again. The iron block was stuffed back into the wooden trough, and then he wound the fine gold wire under the spinning wheel, arranged it in a rough ring, and twisted the two ends of the gold wire together.

After finishing all this, he clapped his hands and said mysteriously: "Next, you have to look carefully, this is the key point I want you to learn today."

Naturally Xu Fuyuan and Xia Yunyi had seen the thin golden thread a long time ago. They thought it was for decoration, but it was also for 'experiment' after a long time. Now the emperor asked them to take a closer look. With puffy eyes, he stared at the emperor's hands seriously.

I saw Zhu Cijiong gently cover the cardboard sprinkled with iron powder back on the wooden board with the iron block, and then grasp the spinning handle of the spinning wheel and spin it vigorously.

A miraculous scene appeared again, the iron powder on the cardboard slowly gathered towards the iron block surrounding the gold thread, and soon formed a regular long strip above the iron block, Zhu Cijiong said while turning the handle : "Fu Zhai stepped forward and flicked the cardboard, just like before."

Hearing this, Xu Fuyuan hurried forward and flicked the cardboard lightly, and the same magnetic force lines appeared on the cardboard as before, but only around the iron block wrapped with gold wire, and there was still no movement above the iron block without gold wire wrapped around it.

At this time, Zhu Cijiong stopped turning the wheel, and said solemnly: "Remember, this is the key point I want you to learn. Now I will explain it to you. You may not understand, but you must remember it and keep it in your heart. , Slowly understand, and one day you will understand."

Then, he pointed to the thin gold wire and said: "This is a thin wire made of gold. Gold, silver, copper, iron and other things actually have one thing in common, that is, they can all conduct electricity. I will give them a name. They are called metals, and those with properties similar to gold are called metals. You should remember that metals have one thing in common, that is, they can all conduct electricity.”

Then, he pointed to the magnet on the wheel and said: "This is a magnet, also called a magnet. You have also seen it just now. There are magnetic field lines around the magnet that are invisible to the naked eye."

Finally, he pointed to the pattern of magnetic field lines on the piece of cardboard that had just been removed, and solemnly said in a majestic tone: "I have done so many experiments to let you understand that when the loop formed by metal is used to cut the magnetic field lines When moving, electricity will be generated in the metal loop, and if the charged metal wire is wound into a coil, it will generate magnetic force, which is the same as that of a magnet, that is to say, electricity and magnetism can be generated together!"

Well, it’s metal, it’s loop, it’s electricity, there are too many new terms, and most ancient people would probably hear them in a cloud, but Xu Fuyuan and Xia Yunyi are not ordinary people. They have quick thinking and logical logic. They are the kind of geniuses who study science, and Zhu Cijiong has done a series of experiments for them to demonstrate.They really understand the principle of mutual generation of electromagnetism!

(End of this chapter)