Chapter 67:

Self-study in the second quarter of the evening.
Wu Jing Sansha took advantage of the teacher's absence, and after completing today's number of questions, he skipped half of the night for self-study and began to discuss their plans.
Chen Jun set up his collar and led the two to the empty basketball court.
It just rained, and there was a basketball on the wet ground. It might be that I forgot to take it back in the afternoon physical education class.
He picked up the basketball, shot a basket easily, frowned a little frustrated, and sighed.
"Oh... You said, Goddess Zhang will have her birthday in two days. What should we give? It's been almost three months since we have been in the small black house together, and the contact information is not available. Alas... Is Goddess Zhang annoying? mine."
The basketball drew a beautiful arc, hit the rim straight, and then fell heavily to the ground. After a few bounces, it rolled lonely into the grass on the side of the playground.
Deng Nian and Cao Zhixue looked at him like that, they really seemed quite disappointed.
Ye suddenly couldn't bear to pit him.
The two looked at each other, and they opened their mouths a little bit hesitantly.
Or, tell him?
It's all about being broken in love, if you make a fool of yourself in public, it seems to be pitiful.
When Cao Zhixue's words reached his throat, he would blurt out.
As a result, at this moment, Chen Jun suddenly slapped his thigh and laughed wildly.
"Puff ha ha ha ha ha Cao Zhixue, I almost forgot, did you watch that video yesterday?"
Cao Zhixue looked stunned, wasn't he still sad a second? The topic jumps so fast?
"Hahahahaha, idiot Cao, you didn't watch the video seriously when you saw it. Did you hear that Goddess Zhang spoke for you when she beat Lin Pingzhi yesterday?"
"Of course I heard, the goddess Zhang is too kind, gentle and kind."
Cao Zhixue recalled with a idiotic look.
He almost lost his confidence yesterday. He would have been lost if he hadn't been praised by the goddess.
Alas, such a beautiful, outstanding and kind-hearted girl, why is she a famous flower?
Still so in full swing, like glue like paint, lingering...
He thought of the scene in the alley and wanted to poke his eyes blind.
Heart hurts.
"Hahahahaha..." Chen Jun was still smiling over there, even running over and pointing at his face to smile, smiling triumphantly and wildly.
"Then did you hear what she said?"
Cao Zhixue shook his head again with a dazed expression.
What, don’t you just praise him for being smart?
Why does he laugh so unpleasantly? So... less beating?
"I went back and listened to it four times. It's absolutely correct. When Goddess Zhang mentioned you, she said,'In my opinion, he is a very smart kid... classmate.' Before she said classmates, she wanted to say'Child 'of."
"Puff ha ha ha ha ha, Dasha Cao, you are finished, you are just a child in the eyes of the goddess! Ha ha ha... child, I am so ridiculous, although I didn’t have the contact information, I was in her eyes, at least It's a man! Grandson Cao, be good, do you want Grandpa to buy you ice cream? Hahahahaha..."
He was shivering with laughter, wiped away the tears from his laughter, and couldn't stand up straight.
Cao Zhixue: "..."
This big, silly, fork!
...He just couldn't bear to pit him? Damn, you have to die! He doesn't have the surname Cao if he doesn't go to death!
He walked over with a dark face and gave Deng Nian a look.
Deng Nian: "..."
Mom, why fool Cao seems a little scary today?
When he was shaking his mind, he heard Cao Zhixue smile very cordially, pretending to be sad, and sighed: "Yes, Chen Jun, I can't catch up, and the three of us rely on you. That's right, Do you remember that the goddess screamed at him just after you and Lin Pingzheng got up yesterday. Isn't she helping you?"
The tone is extremely sincere.
After Chen Jun listened, his smile was stagnant, yes!
It makes sense!
He was silent and began to recall, the more he thought about it, the more he felt it was possible. At that time, he was struggling to leave. Goddess Zhang seemed to give him a soothing look, and then stepped forward to talk to Lin Ping.
If it wasn't for liking him, how could she stand up at that time if she was such a cold person?
Cao Zhixue smiled inwardly, and the fool was about to hook.
Make you laugh at me, smile at me with your nose, and laugh with tears.
I don't cheat you, who?
He poked Deng Nian.
When Deng Nian was said by him, he definitely wanted to watch the excitement.
So he also started to help: "Don't tell me you really, I seem to have this feeling when you say it. Chen Jun, our class is your hottest blood, you dared to talk to the teacher at the very beginning yesterday, I listen to the class The classmate said that Goddess Zhang's ideal type is a passionate boy."
He said, patted Chen Jun on the back: "Brother, you are so funny!"
Cao Zhixue continued to add fire: "I haven't run away, I must like you, bravely go on the ground, the girls are thin-skinned, there will be no shop after this village."
Chen Jun: Lying in a...slot? Happiness comes too suddenly?
The spring breeze is so gentle, and the splendid wildflowers on the side of the playground are sweet.
Spring is here!
Chen Jun wiped his face, picked up the basketball that had fallen to the corner of the playground, stood vigorously outside the three-point line, and shot it out in a handsome posture.
Missed.
He didn't care at all.
The goddess actually...like him?
No wonder, there have been signs of it.
Let’s just say, when he went to ask the boss to ask questions, Goddess Zhang seemed to be looking at them in this direction. Her eyes were tender and worshipful, and a little affectionate. As a result, his eyes just met her, she He hurriedly retracted his sight.
She must have been hit by him and peeked at him, so embarrassed.
God, since the goddess also likes him, are they just happy? The goddess was shy even when she looked at him, she must be thin-skinned, confessing this difficult task must be entrusted to him!
Chen Jun straightened his chest. At this moment, he felt that he had grown up and was a responsible man.
He looked at two good brothers: "I plan to confess this Friday and become the goddess of Saturday for her birthday, so I can spend it with her, buddy, help me!"
After hearing his words, the two looked at each other, and both nodded heavily with solemn eyes.
Chen Jun couldn't help his nose sore, and patted the shoulders of the two of them.
It is worthy of being a good brother who has waved together.
...
On Thursday night self-study, Li Wei gave them the first class in the small class.
He revisited the angular momentum theorem and rotation theorem of rigid bodies.
It was the first time to lecture, but he didn't seem to feel any strangeness at all. The boy was standing in front of the blackboard. He was much taller than Lin Ping. The classmates sitting underneath suddenly felt that the blackboard was a little short in contrast.
The boy's sleeves were rolled up, his clean and strong hand held a chalk, and he wrote a few formulas on the blackboard-all the variables used in this topic and the relationship between them, momentum p, angular momentum L, Moment M, moment of inertia I……
After he finished writing, he drew proper circles at the back of each formula and marked them in order.
After bidding, Zhang Man seemed to smile when he saw him turning his head and looking at her.
Next, the teenager summed up the questions that the boys had asked him some time ago and his own basic question types into several corresponding types.
Then, he began to disassemble the questions and diagrams.
Directly extract the valid information in each subject and the corresponding position in the map, and write the variable label at each corresponding position.
Then link each variable according to the known conditions of the question, and write down a series of corresponding formula labels.
Whether it is a thin rod, a spring, a string, a small ball or an inclined plane, different properties give them different force modes. Soon after analyzing several topics, these objects that caused everyone's headaches were directly transformed into physical symbols.
In this way, a complex and complete physics problem is abstracted into a type problem, broken down into a bunch of physical variables and the relationships between them.
Simple, clear and clear.
Chen Jun opened his mouth, and said "fuck" to express everyone's heart.
Can you do this? Those pictures still have questions. They were stripped of their coats at this moment, clamoring for oneself, which knowledge point, which variable, which formula, all complicated and changeable question types, all returned to the formula area at the top corner of the blackboard.
Nothing is left out.
This...this kind of feeling is as if you originally had a big mess of hairballs on your hands, and what he just did was to find the thread ends, and then easily smoothed all the knots.
Isn't it too comfortable?
The whole classroom was very quiet, the same as when Lin Ping was there. But the difference is that when he was there, he was lifeless and quiet, but now, everyone is shining brightly and swiftly copying the summary on the blackboard, and there is no time to speak quietly.
Fifteen minutes later, everyone who had concluded the summary looked at the boss in front of the blackboard with beaming eyes.
"These are mathematical analyses for several basic types of questions. Of course, the real physical model is very complicated. This set of methods is not suitable for all questions. So I hope that everyone can really understand each formula from a physical point of view. Meaning."
"This subject does not only exist in computing."
As the boy spoke, he began to use various models to explain the physical meaning of each topic and formula.
How to understand the relationship between angular momentum and torque, the relationship between angular momentum and momentum, the differential and integral processes involved in the real model, and what kind of property the moment of inertia is for a particle system...
The formula that had been memorized by rote and mechanically reproduced suddenly became vivid and vivid under his narration. It is no longer forbidden to write mathematical derivation, but a living physical image, from his every sentence, jumping out, intuitively spinning and dancing in front of everyone.
This is physics.
It is not only necessary to use mathematics as a derivation tool, but also to understand the deeper physical meaning.
Many years later, Chen Jun, who was well-known in the field of physics, talked about angular momentum when he was teaching "Mechanics" to his students in a college class. He suddenly remembered that he used to sit in a small classroom in his youth. This lesson I have taken.
The young and promising young professor suddenly got stuck facing the more than one hundred students in the lecture hall.
Over the years, he could still feel the feeling of rapid heartbeat.
In that age when only pursuing exams, the genius boy abandoned derivation and used plain language to tell them about the physical world view, constructing a vivid physical image and frame.
Obviously, from today's point of view, it is a very basic and simple content, but it made him feel that at the time--
It turns out that physics is so beautiful.