Superspace Future Technology

Chapter 71 Why should the lightning rod be needle-pointed?

90.00% of the students who chose the Department of Science and Technology Research are boys. Now there are 51 students in this class, of which there are only 4 girls, and these 4 girls are all relatively average-looking. It is no wonder that people often say that almost all girls in the science class are Tough girl.

Bai Xiaodao chose a seat in the last row and sat down. Soon a teacher in a Chinese tunic suit came in majestically. He was a typical retroist, even his hairstyle and movements were the same as those of decades ago. The leaders and secretaries are exactly the same, especially the pair of round-rimmed glasses, which can be said to be antiques.

This 40-something-year-old teacher is called Cambridge, and his name is exactly the same as that of Cambridge in Xu Zhimo's "Farewell to Cambridge". This name is quite poetic and easy to remember, but it is easier to be ridiculed by others...

Write the word "Kangqiao" on the blackboard. Teacher Kangqiao stood on the podium facing everyone with a serious face. He put his hands behind his back and stood upright like a javelin. Now I am your counselor. Although university study is relatively free, in my class, you only need to remember two points, first, you must not be late and leave early, and second, you must not do anything unrelated to the course! You won’t be using it for my class in the future! Let’s introduce myself briefly from the first group!”

Just after Teacher Kang Qiao finished speaking, the expressions of the others became a little unnatural. It seemed that they knew that this was a very bad-tempered teacher, but they didn't have much complaints about choosing this major.

Soon, it was Bai Xiaodao's turn to introduce himself, but before Bai Xiaodao could speak, Kang Qiao frowned and said first, "Student, why do you sit at the back if you don't sit in so many seats in front?"

I like it, can't I?Bai Xiaodao was also drunk, but out of politeness and respect for his elders, he stood up and said, "Teacher, I don't like places with many people. This place allows me to calm down and think about problems better."

"Well, can you see the blackboard clearly?" Cambridge asked in a flat tone.

"Report teacher, my eyesight is very good! I can see those two moles side by side on your forehead clearly!" After Bai Xiaodao finished speaking, other students in the class noticed that there were really two moles on Teacher Kang Qiao's forehead. Small moles with a width of four to five centimeters.

"Go ahead and introduce yourself!" Kang Qiao said helplessly, thinking that this kid's eyesight is really amazing, and it can be a very good aid for those who are engaged in this kind of technical research.

"My name is Bai Xiaodao, and I'm from Tianhai City. I hope everyone will take care of me!"

Ok?It turned out to be this kid, who is really different. I wonder if it is really what Director Cui said?Kang Qiao thought to himself, he had heard of Bai Xiaodao, the number one scholar in liberal arts, and what made him most curious was that Director Cui said that this guy had a deep understanding of university mathematics, physics and chemistry, so Cambridge's curiosity was immediately aroused What he couldn't understand was that if Bai Xiaodao's grades in mathematics, physics and chemistry were so good, why did he choose liberal arts in high school?
In short, the saying that students with good grades are wonderful is not wrong at all.

Bai Xiaodao's brief self-introduction was quite a sensation. Everyone turned their heads to look at Bai Xiaodao sitting in the last row with some curiosity.
In the Department of Science and Technology Research, this talk is about very profound knowledge of mathematics, physics and chemistry. Even for science students with relatively good grades, it is difficult for them to penetrate the knowledge points.What's more, liberal arts students didn't learn this knowledge in high school, so everyone couldn't figure out whether Bai Xiaodao, a liberal arts student, came here to embarrass himself?
However, there was one person who didn't think so, and that was Pang Jiayu, who was sitting in the first row in the middle. He was Bai Xiaodao's old classmate, and he was also the person present who knew Bai Xiaodao best.

Pang Jiayu is the top student in Huatian No. 651 Middle School with a total score of [-] in the science college entrance examination. It is already very good to get this score in science, but Pang Jiayu's score is only at the bottom of this group of people. It's just above average, and there are many people with higher scores than him.

In addition to Pang Jiayu, two of these people are also classmates of Huatian No. 61 Middle School. They naturally also know the legendary figure Bai Xiaodao. Under Bai Xiaodao's tutoring, 52 of the 500 students in their class scored more than [-] points in the college entrance examination!
Before that, Class Three (2) of Senior High School was an ordinary class with most of them being scumbags. However, under the leadership of Bai Xiaodao, their overall grades in this class were completely inferior to the two top classes in Huatian No. [-] Middle School.

After everyone introduced themselves, Cambridge suddenly wrote a question on the blackboard: Why is the lightning rod made into a needle point? .

"Which classmate can explain?"

Ma Xuedong glanced left and right. He wanted to stand up and answer, but he was worried that he would lose face if he didn't answer well. He had some understanding of the principle of the lightning rod, but he couldn't organize the perfect answer in his mind for a while. .

Everyone quieted down unanimously, as if no one wanted to be the first person to eat crabs.

"Student Bai Xiaodao, please answer." Kang Qiao looked at Bai Xiaodao who was sitting alone at the end, and asked by name directly.

"Heh, this guy is really unlucky." Ma Xuedong secretly smiled, in his opinion, Bai Xiaodao must not be able to answer this question.

"In thunderstorm weather, when a charged cloud layer appears over a high-rise building, a large amount of charge is induced on the lightning rod and the top of the high-rise building. Since the needle of the lightning rod is sharp, the tip of the conductor will accumulate the most charge during electrostatic induction. In this way, the lightning rod will gather Most of electric charge, and lightning rod has formed a capacitor with these charged cloud layers again, because it is point, the two-plate that is this capacitor is very little over against area, electric capacity is also just very little, that is to say that electric charge that it can hold is very little. less. And it has gathered most of the charges, so when there are more charges on the cloud layer, the air between the lightning rod and the cloud layer is easily broken down and becomes a conductor. In this way, the charged cloud layer and the lightning rod form a path, and the lightning rod is Grounded. The lightning rod can lead the charge on the cloud layer into the earth, so that it will not pose a danger to high-rise buildings and ensure its safety. In simple terms, the air becomes a conductor, so that large-scale lightning strikes are converted into small-scale discharges through the lightning rod ?."

Bai Xiaodao eloquently said that although this is a question of common sense in life, it has a lot of knowledge. Many people are ambiguous about the principle of the lightning rod. Explained in such detail.

"That's a good answer, please sit down!" Cambridge nodded in satisfaction, and the other students clapped their hands one after another.

Being robbed of the limelight by Bai Xiaodao, Ma Xuedong's face immediately turned black, thinking that he would have answered first if he knew it earlier. Although he couldn't explain in too much detail, he could still express the general meaning.

"Hey... such a mentally handicapped question, Master Dao, I don't even bother to use the ring computer."

In the answer just now, Bai Xiaodao really didn't use the ring computer to cheat. In his eyes, this question is as simple as eating and sleeping, and he can answer it casually.

(End of this chapter)