"Take a look at this bar magnet. I tied a string to its center and suspended it in the air. When it is still, I call the end that points to the south the south pole of the magnet. The end that points to the north is called the north pole of the magnet. Then, I'll label it with the north pole and south pole labels. Qingque, follow my steps and label the other magnet with the north pole and south pole labels! "
In the Drunken Wind Pavilion, Li Zexuan was holding a bar magnet and conducting the most basic physics experiment for the four of them.
"Good, good, good. Tai, come and try!"
Li Tai had read a lot of the Four Books and Five Classics, but he had never done a real experiment before. He had been watching Li Zexuan play happily from the side and had long been itching for a fight. When he heard this, he immediately rushed over.
Li Zexuan smiled and let the little fatty play by himself. He went to get two small pieces of paper and was about to stick the "N" and "S" poles on the magnet in his hand when he suddenly froze. This was the Tang Dynasty. How could the ancients know about "North" and "South"? If you put "N" and "S" on it, who would know what it meant?
Helplessly, he shook his head and wrote 'N' and 'B' on the north and south poles. He'll just use the pinyin initials of the north and south poles! Sigh, how vexing! Many scientific terms and terms in the future had various English abbreviations. What should he do in the future? Li Zexuan couldn't help but feel a headache coming on. It seemed that there was still a long way to go to raise the level of science and technology in the Great Tang!
"Sir, Tai has also found the north and south poles. Eh? Sir, what do you mean by these words? "
Li Tai's hands-on skills were not bad. It didn't take long for him to find the north and south poles of the other magnet. But when he saw the two letters Li Zexuan had marked, he was immediately confused.
"Qingque, do you still remember the pinyin? 'N' and 'B' are the pinyin initials of the north and south poles. For the sake of convenience, we'll use these two letters to replace the north and south poles in the future! "
Li Zexuan couldn't help but rejoice at his quick-wittedness. Otherwise, how would he explain the 'N' and'S '?
"Oh! I see. Now that you mention it, Tai also feels that it's quite convenient! "
Li Tai suddenly understood. Then he followed suit and marked the north and south poles of the magnet in his hand. At this time, Li Zexuan held two magnets in his hand, looked at the four of them, and said,
"Next, I'm going to tell you a very important theorem, which is that magnetic poles of the same sex repel each other and magnetic poles of the opposite sex attract each other. If you don't believe me, you can try it yourself and see if it's true!"
"Is there such a thing? Let me try! "
Li Yu took two magnets and started the experiment. Although she didn't know pinyin, she could still tell if the two letters were the same.
"It's really like that! Sir, why is that? And what does this have to do with the compass being able to point the way? "
After Li Yu played with the magnets for a while, she tested the result that Li Zexuan predicted. Then she asked.
"Why does the same sex repel each other and the opposite sex attract each other? You can think about this question later. Of course, you can also understand it as the relationship between people. Usually, it's a man and a woman who get married. You've never seen a man marry another man or a woman marry another woman, right?"
Li Zexuan couldn't explain this question clearly. At that time, their physics teacher only said that it was a theorem and asked everyone to remember it. As for why the same sex repel each other and the opposite sex attract each other, he didn't know. He could only say that he didn't understand!
"Haha!"
Li Yu smiled and said, "Sir, this is really interesting!"
"Ahem, as for how this theorem is related to the compass, I can only say that it's very related. In fact, the earth can also be seen as a big magnet. One of its poles is near the geographical north pole, which can also be called the south pole of the geomagnetic field. The other pole is near the geographical south pole, which is the north pole of the geomagnetic field. According to the principle of the same sex repel each other and the opposite sex attract each other, our magnets and magnetic needles can point to the north and south under certain conditions. "
Li Zexuan began to teach them about the geomagnetic field. It was the first time the children heard such a novel theory, and they all widened their eyes.
"How is that possible? How can the earth we're standing on be a magnet? "
Li Tai muttered to himself. His face was full of disbelief. This shocking theory had completely overturned his worldview.
"Haha!"
Li Zexuan smiled and didn't say much. He walked to the nearby tables and started to draw. A real compass used for navigation couldn't be so crude and simple. It didn't have any technical content.
In fact, the core of a compass, other than the magnetic needle, was its central axis. It had to consider the balance of the needle and the friction during rotation.
Li Zexuan designed the central axis as a step axis. He drilled a hole slightly larger than the diameter of the thin end of the step axis at the center of gravity of the magnetic needle. After the magnetic needle was inserted into the thin axis, he tried to deform the thin axis and rivet the magnetic needle onto the thin axis. He controlled the deformation of the thin axis to prevent the magnetic needle from being riveted. At this time, the magnetic needle could rotate around the thin axis, but it couldn't leave the thin axis. As for the cover of the compass, he could only use glass.
In the past, he was lazy and didn't make glass. He didn't expect that he still couldn't avoid glass. This time, he might as well make glass!
Thinking of this, Li Zexuan raised his head and ordered,
"San Bao, go and ask Faubert to come here!"
"Yes, Young Master!"
San Bao responded and hurriedly ran out of the small courtyard to look for Uncle Fu.
After a while, Faubert came in and asked, "Young Master, you were looking for me?"
"Yes, Faubert, take a look and see if this thing can be made."
Li Zexuan handed the drawings of the various parts of the compass to Faubert and said.
Faubert took it and looked at it seriously. After a moment of silence, he finally nodded and said, "It should be possible, but it's very troublesome. Young Master, there are many small and delicate parts in the thing you drew. If you want to make it perfectly, you'll need an old craftsman who has been working for more than ten years!"
Hearing this, Li Zexuan patted his head. He almost forgot that some of the parts in this compass were almost equivalent to a small precision instrument. In a modern industrialized society with all kinds of lathes and machine tools, it would only take a few seconds. However, in ancient times, where craftsmen relied entirely on manual craftsmanship, it was really difficult.
"Then Faubert, quickly gather a group of experienced craftsmen and have them put down their work and concentrate on making a batch of compasses. Oh, I forgot to tell you, this thing is called a compass. It's something that His Majesty urgently needs. This time, the Imperial Court's navy is mainly relying on this thing to determine the direction in the vast sea. Tell the craftsmen to hurry up. If you make one more now, you might be able to save the lives of many people on board! "
Li Zexuan said with a serious expression. If there were difficulties, then they had to overcome them. Although there were no modern craftsmen in ancient times, there were many skilled craftsmen. Many of the ancient handicrafts and buildings could not be made by modern people even if they relied on machinery.
Faubert had thought that Li Zexuan would come today just like before, purely to make some new things for him. He did not expect that Li Zexuan would come with such an important task today. After hearing this, he quickly said with a serious expression,
"Young Master, rest assured that the workshop will work together these few days to make a batch of compasses!"
…
You've already exceeded your reading limit for today. If you want to read more, please log in.
Login
Select text and click 'Report' to let us know about any bad translation.
