Settled in the Tang Dynasty

Chapter 11 Mathematics Lesson [-] of the Early Tang Dynasty

Seeing that Princess Pingyang didn't let the beautiful woman avoid him, Xue Lang didn't say much, and simply said, "General, the student is rude."

Saying that, he stood up, took the drawing and spread it out, and explained directly:
"This is a three-bow composite bed crossbow. The three-bow composite bed crossbow has a maximum range of [-] steps. The advantages of the bed crossbow are that it has a long range and great strength. The city walls rammed with earth can also be destroyed with one shot. It is a sharp weapon that can be used for siege; the disadvantage is that it requires many people to operate and it is not convenient to move.”

After finishing speaking, he took another blueprint and continued to explain: "The crossbow with the divine arm has a range of more than 240 steps. It can be operated by a single person and can shoot through two layers of iron armor. The door, rejecting barbarians from outside, resisting bandits from inside, there is no repayment for saving lives, the students feel uneasy, but they have nothing to gain, if these two blueprints can be used by the princess, that would be the best."

Princess Pingyang was also the one who led the army to fight, and she understood the benefits as soon as she heard it. Her calm and calm eyes finally became a little brighter, and she looked at Xue Lang with burning eyes: "The drawing method of this blueprint is also quite novel. Can you give me some pointers?"

"This is called the three-view drawing method. It is the figure obtained by observing an object from the head-up view, the top view, and the left view. Princess, please take a look..."

Xue Lang stepped forward, spread out the drawing, and explained to Princess Pingyang how to look at the drawing in detail.

Xue Lang started painting in elementary school, and was very interested in design majors. Although he didn't go to university, he learned a lot by himself.

Princess Pingyang pinched the drawing, and touched the paper lightly with her slender fingers: "This paper is also different from the ones I used in Tang Dynasty, and the brush and ink are also strange. Is there a difference in the manufacturing process?"

Xue Lang had seen the red paper given by Licorice, but he didn't know if there was any difference in the writing paper: "General, please take a look at the commonly used paper."

Princess Pingyang took out a piece of paper from the table and handed it to him.

Xue Lang studied painting.Back then, when his parents had no accidents, when he was learning painting from his teacher, he was guided by the teacher to learn about various papers in the first class. When he went out to sketch, he often took Xue Lang to visit various traditional paper-making places.The teacher often said how can a person who is learning to paint not understand paper.

Xue Lang touched it with his hands, and after a glance against the light, he understood: "The princess usually uses hemp paper, and the main material is hemp plants; the students' paper is leather paper, and the main material for making paper is tree bark. As for the pen ,Students use pencils to draw, and pens to write famous thorns. In our place, brushes are called soft pens, and pens are called hard pens. Only those who pursue the art of calligraphy write brush characters, and hard pens are often used , writing is convenient and fast.”

Pen Xue Lang has a pen that he carries with him. He takes it out of his pocket and hands it over and tells him how to unscrew the cap.

Princess Pingyang tried to write on the paper, but it was crooked, obviously not used to it.However, the benefits and convenience of this fountain pen can be seen at a glance.

Princess Pingyang nodded, put down the drawing, and picked up the binoculars: "What is this?"

Xue Lang: "This is called a high-powered telescope."

"Telescope? This is used to climb high and look into the distance? But, what is high magnification?"

Xue Lang explained what a high-power telescope is.Fortunately, he didn't buy one with night vision function. If he bought one with night vision function, it would basically be useless as soon as he travels through time. There is no battery!

"This thing is quite useful on the march."

Princess Pingyang saw the benefits at a glance.Xue Lang said with a smile: "It's really useful. Because of this, I avoided a lot of dangers along the way. Otherwise, let alone returning to the Central Plains, my survival would be a problem."

Princess Pingyang nodded, and she was not in a hurry to try it, but asked Xue Lang: "This thing is quite wonderful, sir, do you know how it is made?"

"The principle of the telescope is very simple. It uses the light refraction of the lens and the principle of small hole imaging. The principle is not difficult, but the problem is the material! When students look at this telescope, they can roughly measure the distance and size. The most important thing is Lens! This is here! The quality of the lens is related to the clarity and distance of the observed things, and distance measurement requires calculation."

"Calculate? How to calculate?"

"This is very simple, just use a formula."

Xue Lang loves cycling, and occasionally climbs a mountain or something. The telescope is a must-have equipment, and the distance measurement calculation was taught to him by his girlfriend's brother.The uncle who didn't make it was from a certain army department, and he was more speculative with Xue Lang. He gave Xue Lang many things to play with, such as sabers and medicines.

Pulling over a piece of paper, Xue Lang took out a pen, wrote down the formula, gave an example, and wrote down the numbers casually——

"and many more!"

Princess Pingyang stopped Xue Lang and pointed to the numbers on the paper: "What does this mean?"

Xue Lang patted his forehead. He remembered to write Chinese characters and numbers when drawing pictures. Now he used to write Arabic numbers when he was doing calculations and demonstrations.

"This is a number, the way Frangji is used to. Because it is more convenient to write, learn, and calculate, so the previous way of writing has also been changed."

While speaking, write out the corresponding Chinese characters and numbers at the same time, which is clear at a glance.

Princess Pingyang took the paper to read, without saying a word, directly took out another piece of paper for Xue Lang, and asked him to calculate on it, and those with numbers and Chinese characters corresponding to them were held in his hand to read.It is very fast to write a calculation demonstration, but it only takes a while, and the examples given together can be understood at a glance.

Princess Pingyang received the two pieces of paper together, put them on the table, gently covered them with jade hands, and asked directly: "Did you learn these in Frangji?"

"Yes. According to the local system, young children enter school at the age of six and are divided into elementary school, middle school, and university. Primary school is divided into six years, and middle school is divided into junior high school and high school, each with three years. In addition to learning ancient classics, you also need to learn mathematics, physics, and chemistry. Waiting for the course."

When Xue Lang said this, not only Princess Pingyang, but even the beautiful women showed interest, turned their eyes, and interjected: "Mathematics, as the name suggests, is the knowledge of exponential calculation, and physics is the principle of knowing things, right?"

"Exactly. I don't know how to call this lady?"

During the Sui and Tang Dynasties, young women were generally called Niangzi.Xue Lang knew this common sense, so he was not afraid of making mistakes.

"This is Liu Shi, the female official of the palace."

"It turned out to be Mrs. Liu. The content of mathematics and physics learning is similar to what Mrs. Liu said."

"What's the chemistry?"

Miss Liu asked curiously.Xue Lang replied with a smile: "It is the principle of studying the changes of objects. For example, why copperware rusts, what is the difference between acid and alkali, and what reactions and changes will occur when the acid and alkali come into contact with different objects, etc."

This female officer Liu is obviously a studious person. Hearing Xue Lang say this, her face was full of fascination: "There are still people who study this kind of knowledge in the world. I really want to see it. Does Mr. Xue Lang have any books?"

Xue Lang smiled: "Are there any books ready-made. I can write them down after I settle down."

Xue Lang, who can remember even a website, naturally has a deeper memory of the chemistry books he has learned, and it is not difficult to write them out.

It is probably because I have never heard of someone coming from such a far away place, and Xue Lang's speech, clothes, words and deeds are all different from Tang people.

Lady Liu asked a lot of questions, starting with food, clothing, housing, and transportation. Xue Lang tried his best to answer in light of the modern situation, telling what he knew, and frankly telling him that he didn't understand when asked about areas he didn't understand.It is God who is omniscient and omnipotent, not man.If you brag and brag, you will break, and if you pretend to be big, you will be struck by lightning.

(End of this chapter)