"Hello everyone, I'm Su Ran, and I hope to make progress with you. Pen, fun, pavilion www. biquge。 info" Su Ran stood up, spoke briefly, and sat down.

"Overdue." The expiration date was even more cold, and he sat down directly after throwing two words.

Teacher Li looked at the two of them, and a hint of interest flashed in his eyes, these two children were quite interesting, and they paused before starting to talk about the class.

Mr. Li's class is actually very interesting, because he knows how to mobilize students' interest, and the idea is very clear, today's physics course is mechanics, in fact, this piece of knowledge is still very good to do the trick, as long as you find a good position to establish the coordinate axis, and then directly list the equation in two directions.

This part of the knowledge is already interesting, and the method taught by the teacher is also very interesting, so everyone is very interested in learning. After talking about the general knowledge points, Mr. Li came up with a comprehensive question for everyone to do, which is actually to combine several of the knowledge points together, and then you need to adapt what you just learned a little.

Everyone quickly solved it, and Mr. Li's face remained unchanged and he came up with another question of increased difficulty, this time there was obviously a trap in the question, but if you were careful, it was actually not difficult, after all, as long as you kept in mind the basic problem, it was not big.

"Remember what I told you, in my class it's actually a battle, me and you. But it doesn't look like everyone's strength is weak. Teacher Li leaned against the lectern, and the teaching stick slapped his palm rhythmically, "Now that you are putting pressure on me, then I will not show mercy to my subordinates in the future, you should be careful." ”

As he spoke, he took out another stack of photocopied papers and handed them to everyone. There are only five questions on it, but each one is more difficult than the other.

The first problem requires a lot of detours, as if you want to solve a puzzle, you need to peel it off layer by layer to see what the content is.

After solving it for a long time, Su Ran found that he had entered a dead end, and the steps he listed were obviously very complicated. I also know that Mr. Li did not ask such questions to let everyone follow the conventional ideas, because such a solution idea is not in line with Mr. Li's style.

Su Ran thought about it carefully, and suddenly his eyes lit up, by the way, since this is the case, we should use the simplest way to solve the seemingly complex problems, and the so-called ever-changing things that Mr. Li often talks about should be like this.

Su Ran first found a suitable position to establish the coordinate axis, and then decomposed the force and listed the formula according to the two directions, in fact, when the problem is viewed from a high place, if you simply look at whether it is black or white, the problem seems to become simpler, because you only need to answer whether it is black or white, that's all.

In this way, in fact, the five questions are just some different changes on a certain basis, as long as you find the key line, the problem actually becomes very simple, of course, to find the most suitable line is actually not so easy. However, after completing these five questions, you will find that Mr. Li is actually very skillful in coming up with the questions, because they all have a very simple common line, and when you go to reminisce, you will have a deeper understanding of this question.

Su Ran raised his head just to meet the gaze of Teacher Li, the teacher's eyes hidden behind him flashed with a slight wisdom, he looked at Su Ran and raised his eyebrows, "Classmate Su Ran, are you ready?" ”