Bringing the Railway to Daming

Chapter 109: Unknown Static Electricity, Homework [Subscribe]

"Yes!"

Li Jinglong thought Liu Kuan was going to teach him how to discharge electricity, so he came over happily.

"What does the teacher need the students to do?" he asked expectantly.

Liu Kuan smiled and said, "Stretch out your hand."

Li Jinglong stretched out his hand expectantly and nervously.

Liu Kuan touched his fingertips with the hand that had just been rubbing the silk. Li Jinglong let out a cry and retracted his hand like a cat whose tail was stepped on.

Then he glared at Liu Kuan's hand and said, "Teacher's hand looks like it has a thorn on it! It pricked me!"

"You were pricked." Liu Kuan raised the silk in his other hand, "Have you forgotten what happened with my hand just now?"

Li Jinglong suddenly realized what was happening and shouted, "Electric shock! Teacher just gave me an electric shock?!"

"good."

After saying that, Liu Kuan rubbed his hand with silk again and then touched Li Jinglong.

Li Jinglong dodged quickly and said fearfully, "Teacher, don't shock me!"

Even ran backwards.

Liu Kuan didn't know whether to laugh or cry, "Stop, didn't you get shocked once just now? Are your hands injured?"

Zhu Yuanzhang also shouted from behind: "Li Jinglong, listen to the teacher!"

Since Zhu Yuanzhang has spoken, how could Li Jinglong dare to run away?
He looked at the finger that had been "pierced" and found that there was no injury at all. Then he carefully returned to Liu Kuan and stretched out his hand.

So I experienced the electric shock feeling of "needles" again.

After Liu Kuan withdrew his hand, he turned to the other students and said, "It feels like being pricked by a needle and slightly numb, just like a mild electric shock. As for what a severe electric shock would feel like, you'll know if you have the chance to see someone who has been struck by lightning."

"One more question - why is there electricity in the teacher's hands?"

Everyone raised their hands immediately, even Li Jinglong who was sitting at the podium.

Liu Kuan looked at him and said, "Okay, considering that you cooperated with the experiment just now, I'll give you another chance."

Li Jinglong took it seriously.

He recalled what Liu Kuan had said before the experiment, as well as the experiment just now, and then looked at the silk and said, "It's because the teacher's hand rubbed against the silk!"

Liu Kuan smiled and nodded. "That's a good answer. It's because my hands rubbed against the silk that they became charged. This also means that electricity is most likely generated by friction."

"Then another question arises: why does friction generate electric current?"

Everyone in the hall couldn't help but follow Liu Kuan's guidance and think about this question, and there was a moment of extraordinary silence.

However, after several breaths, no one raised their hand to answer.

At this time, Liu Kuan said, "This question involves the essence of electricity, that is, the truth behind the generation of lightning. It is quite complicated. It is normal that you can't come up with an answer right now."

"Remember, on the path of natural science, if you encounter a problem that you have no idea about at the moment, you can put it aside for now. Once we have more relevant knowledge, we can study it again."

Then, Liu Kuan signaled Li Jinglong to close the palace door.

When Li Jinglong came back, Liu Kuan asked, "Are your hands sweating?"

Li Jinglong shook his head, "Teacher, no."

Liu Kuan said, "In addition to requiring items made of special materials like silk, this experiment also requires dry hands. Next, let Li Jinglong repeat the experiment for us."

After saying that, Liu Kuan handed over the silk.

Li Jinglong stretched out his hands and took it with extreme respect, as if he was receiving a magic weapon from an immortal.

Liu Kuan was a little speechless when he saw it, and said: "This is just a piece of ordinary silk. Don't waste time, just rub the silk with your palm."

Li Jinglong, who rarely gets nervous in lectures, was nervous at this moment.

He carefully grasped the silk with one hand and rubbed it quickly with the other.

Liu Kuan blew out the candle, and immediately others saw that a lot of electric sparks were also generated on Li Jinglong's palms and silk.

"Oh my God, Brother Jinglong can also emit electricity!" Little Zhu Zhi exclaimed again in the darkness.

Liu Kuan said, "Students, don't just be surprised. Observe carefully—what's the difference between the electricity obtained by this experiment and lightning?"

"There is no sound, it looks very small and not very powerful." Zhu Tan's voice came directly from the darkness.

"Good answer, 6 points."

As he spoke, Liu Kuan relit the candle.

Seeing that Li Jinglong was still happily rubbing the silk, Liu Kuan said, "Li Jinglong, slow down your rubbing movements. The other students continue to observe."

Li Jinglong did as he was told.

Before the other students could see clearly, he realized it first and shouted in surprise, "Teacher, my hands seem to be able to suck up silk!"

He excitedly opened his palms wider to make the phenomenon more obvious, but saw the silk fall again.

Liu Kuan took the silk and said to Li Jinglong, "Untie your bun."

As the son of a duke, Li Jinglong did not wear a bun, but like the princes and grandchildren of the emperor, he tied his hair up early and wore a golden and jade hair crown.

Hearing this, he began to feel a little helpless, because he had always been served by others and had never taken off his hair crown by himself.

But soon he pulled off the crown and let his hair down completely.

Not to mention, he was born handsome, with red lips and white teeth, and his disheveled hair made him look even more handsome. If he were in the future, it would probably make fujoshi excited and cheer.

At this moment, no one paid any attention to this. Everyone stared at Liu Kuan, who brought the silk close to Li Jinglong's head, only an inch away, and unexpectedly attracted several strands of hair to the silk.

Liu Kuan said: "Obviously, the electricity generated by friction also has a certain adsorption force, which can attract certain things."

"Because the electricity generated by this friction is silent, it can be called static electricity. The experimental phenomenon just now can also be called an 'electrostatic reaction.'"

"In fact, static electricity reactions are quite common in our lives. Think back, students, when have you seen them?"

In Liu Kuan's opinion, this was a very simple question, and he thought that many people would raise their hands again.

Unexpectedly, these princes and nobles were thinking about it for a while, and no one answered.

Liu Kuan thought about it and suddenly understood.

These children did not need to comb their hair or dress themselves, and the combs used at that time were mostly wooden or ivory, so static electricity was unlikely to occur. Even if it did occur, it would be difficult for the person whose hair was being combed to notice it through the bronze mirror.

As for dressing—how could these children dress or undress in the dark? They were all woken up with lights on and waited on by palace servants.

What's more, most clothes in ancient times were loose, so static electricity reactions were not likely to occur when putting on or taking off clothes.

The reason why Old Zhu and Little Zhu were so surprised by the electrostatic reaction test was probably for a similar reason.

Not to mention Zhu Biao. Old Zhu couldn't afford silk clothes before. Once he got used to wearing silk clothes, he probably wouldn't get up and dress himself at night - even if he did, at least there would be someone to light the lamp for him in advance.

In this case, it is not surprising that these people do not notice the phenomenon of static electricity in their lives.

After about two breaths, Zhu Tan raised his hand.

After he stood up, he said, "Teacher, since rubbing silk can generate electricity, then it should also produce static electricity when wearing clothes, right?"

Liu Kuan nodded. "You're right about one thing. Can you think of any others?"

Zhu Tan looked as if he was racking his brains. After a moment, he tentatively asked, "While you were scratching your head?"

Liu Kuan smiled and said, "You're half right - to be more precise, it's when combing hair. Of course, they don't use wooden or ivory combs, but poor people comb their hair with their hands, which is actually similar to scratching their heads."

"Given your age and life experience, it's not easy for you to think of these two points, so I'll give you another 7 points."

After saying that, Zhu Tan’s credits were changed to 29 points.

Seeing this, Zhu Tan was both happy and felt a sense of loneliness as a master.

Liu Kuan turned around and saw Li Jinglong looking at him eagerly, so he smiled and said, "Student Li Jinglong just cooperated with the teacher's experiments twice and answered a question, so he got a total of 12 points."

Then he filled in Li Jinglong's name and credits on one side of the blackboard.

Li Jinglong was immediately overjoyed, with a smile on his face.

Liu Kuan gestured to Li Jinglong to open the hall door and return to his seat. He then looked around at the students in the hall and said, "Since the phenomenon of electrostatic reaction exists in daily life, did our ancestors discover it long ago?"

"You don't have to answer so quickly, because this is one of the homework assignments the teacher has given you today."

"When you go down, you can look for ancient books to see if the ancients recorded any reactions to static electricity."

"In addition, we have previously deduced in detail the process of how people use fire. I hope that after going back, the students can write a short essay describing this process."

"This short article does not require literary grace; even plain language is acceptable. What is required is simplicity, comprehension, logical coherence, and clear organization."

"This is the second assignment—students under 8 don't have to do it. I'll grade the best work later, and you can just copy it."

Having said that, Liu Kuan picked up the chalk and wrote a few lines of big words on the blackboard.

Turning around, he pointed to the blackboard and said, "Through today's science lesson, we can conclude that the path to exploring natural sciences can be guided by these sixteen words."

“Observe carefully, think deeply, make bold assumptions, and verify carefully!”

"After gaining some natural science principles through these sixteen-character guidelines, we still need to do another thing, which is to apply them to real life, to benefit the people and even strengthen and enrich our country!"

After saying that, Liu Kuan wrote the four big words "practical application" on the blackboard.

He found a piece of red chalk and underlined the twenty characters. He said, "Copy down all twenty characters. I'll be testing you in the next class."

After giving the students two or three minutes to take notes, Liu Kuan continued, "Finally, I'll leave you with a question to ponder. In addition to discussing how people use fire, today's class mainly focused on lightning phenomena and electrostatic reactions."

"When you go down, you can find some silk or comb your mother's hair to test the electrostatic reaction phenomenon."

"The question is about lightning. A significant number of fires in large buildings are caused by lightning strikes. Imperial palaces throughout history have often been destroyed by lightning."

"So why does lightning strike buildings? Is there any way to prevent buildings from being damaged by lightning?"

"In the next class, if any student can answer this question well, they will receive a considerable amount of credits at once."

After hearing what Liu Kuan said, some of the princes and sons began to think subconsciously, while others, such as Zhu Tan, became excited and regarded the credits as something in their pockets.

At this time, Liu Kuan showed another strange smile and said, "If you students have no idea how to solve this problem, you can ask the master carpenter who is responsible for building the imperial palace. You may get some unexpected results."

"Okay, that's all for today's class. get out of class dismissed!"

Perhaps he was so absorbed in thinking that Zhu Xiongying paused for a moment before standing up and shouting, "Stand up!"

Then more than a dozen students in the main hall stood up and shouted together, "Goodbye, teacher!"

"Goodbye, classmates!"

After saying that, Liu Kuan packed up the bag of things he brought with him, walked out of the main hall, and let out a breath.

The students were still inside, but Lao Zhu and Xiao Zhu had already followed them out.

After walking a few steps, Old Zhu asked without hesitation, "Liu Kuan, according to what you said today, the lightning strike must not be a punishment from heaven for someone's evil deeds or the emperor's mistakes?"

　First update.

　　
　
(End of this chapter)