Scholar’s Starry Sea

The camp is located in a suburban area. After all the students got off the bus, they spent about two hours in the room to put their luggage, eat, and get acquainted with the whole school.

Finally, in a classroom, members of the 12 provincial teams were seated one after another according to the pre-prepared seating plan, and took out their pencil cases and notebooks.

On the podium, Wei Tianshuo drank a sip of tea to moisturize his throat, then took out a brand-new chalk and wrote a line on the blackboard.

[Basic rules of the finals]

After writing, turn around and look at the students below: "I believe most of the students sitting below already know the rules of the finals very well, but even You know it, and listen to me again."

"First of all!"

Wei Tianshuo suddenly raised his voice by two notches, almost shocking Wu Bin. Others The reaction was similar, and they sat up straight and continued to listen.

"Before this, I want to give you a general idea of ​​the difficulty of the finals. Here I will describe it to you sideways. There are two points in total."

Wei Tianshuo raised his index finger: "First point, as long as you can get any place in the finals, then the first semester of Beijing University has accounted for 4 credits of mechanics. You can take the exam directly without listening."

The students below are nodded.

"As for the other point, I believe you will be very clear. As long as you get the gold medal, when you are against the guest, all the admission notices of the domestic universities will be placed in front of you, and you can choose."

"This is naturally a recognition of your level of study. It represents that among this group of high school students across the country, in terms of Physics knowledge, no one can match yours!"

Although Wu Bin understood these words a long time ago, listening to Wei Tianshuo said it, there was still a feeling of enthusiasm. I believe the other students are the same.

"Does it sound beautiful? However, the more beautiful things are competing for, the more people naturally compete. The difficulty of the semifinals is more than that of the preliminaries. I believe you all understand it well, so I can know now I’m telling you that the difficulty of the final is much more difficult than that of the rematch, and your opponent will also be promoted to the national level. I don’t need me to tell you how powerful you are."

"Every question in the finals was created to make things difficult for you. Some ideas may not be found in all the puzzle collections and real questions. You can only solve them with your own knowledge, without any The routine can be moved."

After saying that, Wei Tianshuo glanced down and found that most of the classmates were in a calm state. It is estimated that many people have said these things to them, but there are A student behaves strangely, he is actually smiling, and it is the kind of smile with a little excitement.

'It should be called Wu Bin, right...Interesting. '

On the bus, Wei Tianshuo has already known all his classmates, and although he has only been with each other for a few hours, he has already remembered his name.

After reading the reactions of the students, Wei Tianshuo continued.

"I believe you have practiced before to solve all problems of the same type in one way, and the purpose of our training camp is to make you one step further, so that you can read the papers After finishing the question, I immediately understand which solutions are in the mind of the person who asked the question, not which solutions the question really has. This will help you to improve your efficiency."

The students below It was nodded again for a while.

"Okay, I have a set of papers, you do it first." After Wei Tianshuo finished speaking, he took out a stack of papers from the podium.

Students who have to shout "Ah" when they do not agree with each other are unlikely to sit in this classroom, so everyone in the classroom heard that they had to do the papers. Take out the pen, turn on the calculator, and enter the state of preparation.

Wu Bin got the paper and started to review the questions habitually, and found that in terms of difficulty, he did not have the Hell Level as he imagined. They were all relatively common question types.

"Okay, let's do it." Wei Tianshuo announced after looking at his watch.

So, the only sound left in the classroom is the friction between the pen tip and the paper.

"Stop writing."

One hour later, when he was working on the fifth mechanics problem at full power, he kept walking around Wei Tianshuo, who was on patrol. Suddenly shouted.

'Gan...No way? Did everyone else finish it? '

After thinking about Wu Bin lifts the head moved towards, I looked around and found that other people looked around like him, and finally felt relieved a lot.

At this time, Wei Tianshuo opened the mouth and said: "Don't be nervous, you should also understand the difficulty of this paper, there is no problem, the function is only to test your efficiency in doing the questions."

Speaking of Wei Tianshuo, he glanced at his watch: "So far, the students in this room can basically say that the time for each question is controlled within 15 minutes, which is very good."

Most of the classmates were relieved, Wei Tianshuo laughed in his heart, and it seemed that all of them were very competitive.

"Then I have finished all the prerequisites, and now I officially start talking about the finals."

"The total score of the finals is still 200 points, and the experimental questions still account for 60 points, but The experimental questions for the finals will not be selected from any textbooks. They are all direct propositions. In terms of difficulty, let’s take last year’s questions as an example." .

【Using the electronic components in the "Assembled Power Component Box", design a rectifier and filter circuit that can convert AC voltage to DC voltage with the greatest efficiency, and connect and assemble the designed circuit to make it a DC power supply]

After finishing the experiment requirements, Wei Tianshuo clicked the first question.

【Draw the design circuit diagram, assemble and measure. 】

"Here, do you have any ideas?"

When Wei Tianshuo wrote the question, Wu Bin was naturally already thinking.

'First input the AC voltage of 12V, then use the bridge rectification, and then draw the π filter circuit...'

"Wu Bin, this question, you come up and do it."

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While Wu Bin was thinking, Wei Tianshuo suddenly shouted.

Wu Bin nodded, stepped onto the podium, took the chalk that Wei Tianshuo handed him and began to draw.

(This is a circuit diagram, please raise your claw if you see it.)

More than ten minutes later, Wu Bin patted his hand and said to the teacher: "The drawing is done, teacher. "

Wei Tianshuo smiled and nodded after reading, "Explain the working principle of your circuit diagram."

"Okay." Wu Bin nodded began to point to the picture introduced: "12V The AC voltage passes through a bridge rectifier circuit composed of 4 diodes and becomes a DC pulsating voltage, and then passes through a π-type filter circuit composed of electrolytic capacitors and resistors."

Speaking Wu Bin made a reduced Gesture, "At this point, the amplitude of the voltage pulsation will be greatly reduced, and it will become a DC stabilized power supply that can be used for load."

Wei Tianshuo satisfied nodded and said: "Very good, 4 points for you I have already got it, and then as long as you clarify the role of each component in the circuit, then you can take home 5 points for this question."