future library.

Chapter 42 Star Alliance Level 3
"Tianping?" Xiang Xin looked at Cheng Jinzhou suspiciously and said, "If what you mean is the balance that was given to you last time, it is a very good one."

"I know, I know." Cheng Jinzhou was cheerful, secretly glanced at the content on the face, and said with a smile: "Recently, my hands are itchy and I want to try to make a balance by myself, but I don't understand many things ..."

Xiang Xin showed a trace of disapproval and said: "The balance is something that only professional star warlocks can make. You just need to know how to use it now."

She actually wanted to say: You don't even need to pay too much attention to using it.

People who have been indoctrinated with the greatness of astrology since childhood have a religious obsession with astrology, a religious devotion to rank, and religious discrimination against the weak...

Clearly feeling this kind of discrimination made Cheng Jinzhou very uncomfortable. He was just looking for a reason at first, but now he was very unhappy with the other party's attitude and said with a sour tone: "I don't think it is so difficult to be a balance. If With enough materials, it was easily done."

"I don't know much about it." Xiang Xin said mercilessly: "A balance is not simply a thing that can be measured by placing a bar in the center, and the distance between the two sides is equal. Complicated mathematics..."

"It's just a balance of torque." Cheng Jinzhou shrugged his shoulders and said, "You just want to say that if you move an object for a certain distance, the torque it produces should be the same, so the two sides of the balance should have the same length..."

Xiang Xin's eyes were as round as her bald head.

The so-called moment balance is exactly the principle of leverage.Archimedes said: Give me a lever and I can lift the earth. This refers to the lever principle: Theoretically, if a horizontal bar is placed on the fulcrum, in order to balance the two sections of the fulcrum, the farther away from the fulcrum the farther the bar is from the fulcrum. The place is less laborious.

Ordinary people know from common sense that as long as the lengths of both ends of the crossbar are equal, the two ends can be balanced. However, in actual use, the two sides are often unbalanced. In this case, you need to know the relationship between distance and mass - distance multiplied by mass. It is equal to the distance multiplied by the mass. It is easy to say, but it is not easy to prove.

The main purpose of the balance that can be used is to measure the mass, and in order to ensure its accuracy, the most common pallet balance can not only use weights - the floating code with an order of magnitude less per unit mass (Note 1) is also a must for measurement - - It uses the calculation formula of the leverage principle.

Being said to be the most proud part, Xiang Xin's sneer also subsided, and at this moment she began to admire the master's vision again.

Cheng Jinzhou raised his eyebrows provocatively.Compared to occultism, he is at the elementary school level, but compared to these basic knowledge, the earth technology that has been honed over time can completely abuse primitive people.Remembering that the newly obtained "Mechanical Measurement" was the high-end knowledge of this era, he couldn't help but show it off and said: "Do you know how to determine the position of equilibrium?"

"The weight is the same." Xiang Xin has long been familiar with these contents.

Cheng Jinzhou laughed deliberately: "Superficial."

"What did you say?" Xiang Xin's right shoulder began to glow again.

Cheng Jinzhou took a step back, and said with a strong face: "You want to use force to explain the problem?"

Xiang Xin snorted, shook his arm, the light went out, and continued to hold his head high and said: "If you can't tell me something, I will trouble you again."

"How difficult can it be?" Cheng Jinzhou twitched his lips, picked up a straw, held it horizontally in his hand, and said: "If you want to completely balance the two sides, this simplest balance is the same as nothing. There is no need to discuss it, but If it has a certain angle of inclination."

Cheng Jinzhou slowly placed the wheat straw at an angle of 45 degrees from the top right to the bottom left, and said: "Look now, the lever actually has an angle to the ground. At this time, the torque is no longer a matter of length and mass, and a 45 degree angle should be added. degrees in trigonometric values, right?"

Mathematics is the exercise of discovering that the old method is invalid in the constant pursuit of precision, then designing a compensation method, and finally re-invalidating.

The principle of leverage is very simple, and humans knew it before BC, but when it is applied to trigonometric functions, it needs 1000 years of development.

Xiang Xin understood the disadvantages of ordinary scales, but she didn't expect that Cheng Jinzhou also knew about it, and was stunned for a while.

This is a teenager!Xiang Xin secretly estimated, thinking back to whether he was so outstanding when he was a teenager...

The two looked at each other for a moment, Xiang Xin raised his chin again, and said, "I'll just bring the Astromancer material with me, if it's not enough, I'll buy it later. If you can make one..."

"I won't go to Nanling." Nanling is the domain of the king of Nanling County. Even if there is no Sith Temple, there are two perverted big and small Zhao, Cheng Jinzhou would not want to find it uncomfortable.

"Although I can't change your father's decision, I will persuade him if you can really complete a high-precision balance." Xiang Xin has already looked at Cheng Jinzhou with a straight-up attitude. Regarding the many skills in the process of making the balance, It is also kept secret in the Astromancer Association. In other words, she actually does not know how to make a high-precision balance, and the other party can tell the moment balance, which is already beyond the scope of ordinary students.

Cheng Jinzhou snorted indifferently and said: "This bet is really easy for you, so let me say, you do it."

His hands-on ability is limited compared to middle school students, a real dude, never worried about exams.

Instead, Xiang Xin raised his head in surprise, and began to doubt Cheng Jinzhou's generosity again.

"Okay, I still have something to do here, you go out first." Cheng Jinzhou pretended to chase people away, he did have 1 Star Alliance point to upgrade.

With his momentum weakened, the young first-level star warlock couldn't say anything and left the granary obediently. His attitude of being arrogant at first and respectful at the end made the boys outside look at each other.

Cheng Jinzhou narrowed his eyes and smiled, and said to the ring with a sense of success: "Let's continue."

"3 words." Customer service 010 was already impatient with the wait.

"There can't be so many words." Cheng Jinzhou wiped the sweat from his forehead and said, "The star warlock just saw the situation in the granary. He suddenly lost a lot and will be discovered."

3 words, but it requires 60 star yuan of food. 6 tons of food, which is 6 cubic meters, can be easily discovered.

Customer service 010 said impatiently: "1.3 words. Are you sure?"

"That's it." Cheng Jinzhou was actually very anxious.

""My Days in Tehran"" the voice of customer service 010 said coldly: "Congratulations, the Star Alliance level has been raised to 3."

Cheng Jinzhou slammed open the door of the granary, and the noon sun came directly at him, and a feeling of enlightenment emerged spontaneously.

"The era of mathematics, my era." Cheng Jinzhou thought silently and nodded silently.

……

Swimming weight: In the use of the balance, the smallest weight can be 1 gram. If it is smaller, the daily use will make it inaccurate. For this reason, we use the principle of leverage to make a larger weight fixed on the balance , capable of displaying smaller precisions, such as 0.1 grams.

……

(End of this chapter)